diff --git a/src/AIS/AIS.hxx b/src/AIS/AIS.hxx
index 579f156194..1716313618 100644
--- a/src/AIS/AIS.hxx
+++ b/src/AIS/AIS.hxx
@@ -57,7 +57,7 @@
 //! To facilitate management, each object and each construction element has a selection priority.
 //! There are also means to modify the default priority.
 //! To define an environment of dynamic detection, you can use standard filter classes or create your own.
-//! A filter questions the owner of the sensitive primitive to determine if it has the the desired qualities.
+//! A filter questions the owner of the sensitive primitive to determine if it has the desired qualities.
 //! If it answers positively, it is kept. If not, it is rejected.
 //! The standard filters supplied in AIS include:
 //! - AIS_AttributeFilter
diff --git a/src/AdvApp2Var/AdvApp2Var_ApproxF2var.cxx b/src/AdvApp2Var/AdvApp2Var_ApproxF2var.cxx
index 85a79ad819..c8595771a8 100644
--- a/src/AdvApp2Var/AdvApp2Var_ApproxF2var.cxx
+++ b/src/AdvApp2Var/AdvApp2Var_ApproxF2var.cxx
@@ -5782,11 +5782,11 @@ int mma2er1_(integer *ndjacu,
 /*     PATJAC: Table of coeff. of square of approximation with */
 /*             constraints of order IORDRU by U and IORDRV by V. */
 /*     VECERR: Auxiliary vector. */
-/*     ERREUR: MAX Error commited during removal of ALREADY CALCULATED coeff of PATJAC */
+/*     ERREUR: MAX Error committed during removal of ALREADY CALCULATED coeff of PATJAC */
 
 /*     OUTPUT ARGUMENTS  : */
 /*     ------------------- */
-/*     ERREUR: MAX Error commited during removal of coeff of PATJAC */
+/*     ERREUR: MAX Error committed during removal of coeff of PATJAC */
 /*             of indices from MINDGU to MAXDGU by U and from MINDGV to MAXDGV by V */
 /*             THEN the already calculated error. */
 
@@ -5949,11 +5949,11 @@ int mma2er2_(integer *ndjacu,
 /*             constraints of order IORDRU by U and IORDRV by V. */
 /*     EPMSCUT: Tolerance of approximation. */
 /*     VECERR: Auxiliary vector. */
-/*     ERREUR: MAX Error commited ALREADY CALCULATED  */
+/*     ERREUR: MAX Error committed ALREADY CALCULATED  */
 
 /*     OUTPUT ARGUMENTS  : */
 /*     ------------------- */
-/*     ERREUR: MAX Error commited by preserving only coeff of PATJAC */
+/*     ERREUR: MAX Error committed by preserving only coeff of PATJAC */
 /*             of indices from 0 to NEWDGU by U and from 0 to NEWDGV by V */
 /*             PLUS the already calculated error. */
 /* NEWDGU: Min. Degree by U such as the square of approximation */
@@ -7281,7 +7281,7 @@ int mma2moy_(integer *ndgumx,
 
 /*     OUTPUT ARGUMENTS : */
 /*     ------------------- */
-/*     ERRMOY: Average error commited by preserving only the coeff of */
+/*     ERRMOY: Average error committed by preserving only the coeff of */
 /*             PATJAC 2*(IORDRU+1) in MINDGU by U and 2*(IORDRV+1) in MINDGV by V. */
 
 /*     COMMONS USED   : */
diff --git a/src/Approx/Approx_SweepApproximation.cxx b/src/Approx/Approx_SweepApproximation.cxx
index a12fc94c69..b5cc429a78 100644
--- a/src/Approx/Approx_SweepApproximation.cxx
+++ b/src/Approx/Approx_SweepApproximation.cxx
@@ -120,7 +120,7 @@ void Approx_SweepApproximation::Perform(const Standard_Real First,
    Translation.SetXYZ
      (myFunc->BarycentreOfSurf().XYZ());
    for (ii=1; ii<=Num3DSS; ii++) {
-     Tol =  ThreeDTol->Value(ii)/2; // To take accout of the error on the final result.
+     Tol =  ThreeDTol->Value(ii)/2; // To take account of the error on the final result.
      OneDTol->SetValue(ii, Tol * Wmin(ii) / Size);
      Tol *= Wmin(ii); //Factor of projection
      ThreeDTol->SetValue(ii, Max(Tol, 1.e-20) );
diff --git a/src/BOPDS/BOPDS_Interf.hxx b/src/BOPDS/BOPDS_Interf.hxx
index 2e47700829..601d38e6df 100644
--- a/src/BOPDS/BOPDS_Interf.hxx
+++ b/src/BOPDS/BOPDS_Interf.hxx
@@ -21,7 +21,7 @@
 #include <BOPDS_VectorOfPoint.hxx>
 
 /**
- * The class BOPDS_Interf is is to store the information about
+ * The class BOPDS_Interf stores the information about
  * the interference between two shapes. 
  * The class BOPDS_Interf is root class 
  *
@@ -191,7 +191,7 @@ class BOPDS_Interf  {
   Handle(NCollection_BaseAllocator) myAllocator;
 };
 /**
- * The class BOPDS_InterfVV is is to store the information about
+ * The class BOPDS_InterfVV stores the information about
  * the interference of the type vertex/vertex. 
 */
 //=======================================================================
@@ -224,7 +224,7 @@ class BOPDS_InterfVV  : public BOPDS_Interf {
   //
 };
 /**
- * The class BOPDS_InterfVE is is to store the information about
+ * The class BOPDS_InterfVE stores the information about
  * the interference of the type vertex/edge. 
 */
 //=======================================================================
@@ -289,7 +289,7 @@ class BOPDS_InterfVE  : public BOPDS_Interf {
   
 };
 /**
- * The class BOPDS_InterfVF is is to store the information about
+ * The class BOPDS_InterfVF stores the information about
  * the interference of the type vertex/face 
 */
 //=======================================================================
@@ -362,7 +362,7 @@ class BOPDS_InterfVF  : public BOPDS_Interf {
       
 };
 /**
- * The class BOPDS_InterfEE is is to store the information about
+ * The class BOPDS_InterfEE stores the information about
  * the interference of the type edge/edge. 
 */
 //=======================================================================
@@ -417,7 +417,7 @@ class BOPDS_InterfEE  : public BOPDS_Interf {
   IntTools_CommonPrt myCommonPart;
 };
 /**
- * The class BOPDS_InterfEF is is to store the information about
+ * The class BOPDS_InterfEF stores the information about
  * the interference of the type edge/face. 
 */
 //=======================================================================
@@ -477,7 +477,7 @@ class BOPDS_InterfEF  : public BOPDS_Interf {
   IntTools_CommonPrt myCommonPart;
 }
 /**
- * The class BOPDS_InterfFF is is to store the information about
+ * The class BOPDS_InterfFF stores the information about
  * the interference of the type face/face. 
 */;
 //=======================================================================
@@ -588,7 +588,7 @@ class BOPDS_InterfFF  : public BOPDS_Interf {
 };
 
 /**
- * The class BOPDS_InterfVZ is is to store the information about
+ * The class BOPDS_InterfVZ stores the information about
  * the interference of the type vertex/solid. 
 */
 //=======================================================================
@@ -621,7 +621,7 @@ class BOPDS_InterfVZ  : public BOPDS_Interf {
   //
 };
 /**
- * The class BOPDS_InterfEZ is is to store the information about
+ * The class BOPDS_InterfEZ stores the information about
  * the interference of the type edge/solid. 
 */
 //=======================================================================
@@ -654,7 +654,7 @@ class BOPDS_InterfEZ  : public BOPDS_Interf {
   //
 };
 /**
- * The class BOPDS_InterfFZ is is to store the information about
+ * The class BOPDS_InterfFZ stores the information about
  * the interference of the type face/solid. 
 */
 //=======================================================================
@@ -687,7 +687,7 @@ class BOPDS_InterfFZ  : public BOPDS_Interf {
   //
 };
 /**
- * The class BOPDS_InterfZZ is is to store the information about
+ * The class BOPDS_InterfZZ stores the information about
  * the interference of the type solid/solid. 
 */
 //=======================================================================
diff --git a/src/BOPDS/BOPDS_ShapeInfo.hxx b/src/BOPDS/BOPDS_ShapeInfo.hxx
index d454ed3789..f2babc6253 100644
--- a/src/BOPDS/BOPDS_ShapeInfo.hxx
+++ b/src/BOPDS/BOPDS_ShapeInfo.hxx
@@ -128,7 +128,7 @@ public:
 
   //! Query
   //! Returns true if there is flag.
-  //! Returns the the  flag theFlag
+  //! Returns the flag theFlag
     Standard_Boolean HasFlag (Standard_Integer& theFlag) const;
   
 
diff --git a/src/BRep/BRep_Builder.cxx b/src/BRep/BRep_Builder.cxx
index 272f2fca88..2e71609922 100644
--- a/src/BRep/BRep_Builder.cxx
+++ b/src/BRep/BRep_Builder.cxx
@@ -118,7 +118,7 @@ static void UpdateCurves(BRep_ListOfCurveRepresentation& lcr,
       if (GC->IsCurve3D()) {
 //      if (!C.IsNull()) { //xpu031198, edge degeneree
 
-        // xpu151298 : parameters can be setted for null curves
+        // xpu151298 : parameters can be set for null curves
         //             see lbo & flo, to determine whether range is defined
         //             compare first and last parameters with default values.
         GC->Range(f, l);
@@ -185,7 +185,7 @@ static void UpdateCurves(BRep_ListOfCurveRepresentation& lcr,
       if (GC->IsCurve3D()) {
 //      if (!C.IsNull()) { //xpu031198, edge degeneree
 
-        // xpu151298 : parameters can be setted for null curves
+        // xpu151298 : parameters can be set for null curves
         //             see lbo & flo, to determine whether range is defined
         //             compare first and last parameters with default values.
         GC->Range(f, l);
diff --git a/src/BRepAdaptor/BRepAdaptor_CompCurve.hxx b/src/BRepAdaptor/BRepAdaptor_CompCurve.hxx
index 87efb3f294..cf772a41a9 100644
--- a/src/BRepAdaptor/BRepAdaptor_CompCurve.hxx
+++ b/src/BRepAdaptor/BRepAdaptor_CompCurve.hxx
@@ -70,7 +70,7 @@ public:
   
   Standard_EXPORT BRepAdaptor_CompCurve(const TopoDS_Wire& W, const Standard_Boolean KnotByCurvilinearAbcissa = Standard_False);
   
-  //! Creates a Curve  to  acces to the geometry of edge
+  //! Creates a Curve  to  access the geometry of edge
   //! <W>.
   Standard_EXPORT BRepAdaptor_CompCurve(const TopoDS_Wire& W, const Standard_Boolean KnotByCurvilinearAbcissa, const Standard_Real First, const Standard_Real Last, const Standard_Real Tol);
   
diff --git a/src/BRepAdaptor/BRepAdaptor_Curve.hxx b/src/BRepAdaptor/BRepAdaptor_Curve.hxx
index 3cbfb2f663..ded2fda66c 100644
--- a/src/BRepAdaptor/BRepAdaptor_Curve.hxx
+++ b/src/BRepAdaptor/BRepAdaptor_Curve.hxx
@@ -71,11 +71,11 @@ public:
   //! Creates an undefined Curve with no Edge loaded.
   Standard_EXPORT BRepAdaptor_Curve();
   
-  //! Creates a Curve  to  acces to the geometry of edge
+  //! Creates a Curve  to  access the geometry of edge
   //! <E>.
   Standard_EXPORT BRepAdaptor_Curve(const TopoDS_Edge& E);
   
-  //! Creates a Curve to acces to  the geometry  of edge
+  //! Creates a Curve to access  the geometry  of edge
   //! <E>.   The geometry  will   be  computed using the
   //! parametric curve of <E> on the face  <F>. An Error
   //! is  raised if  the edge does  not have a pcurve on
@@ -85,11 +85,11 @@ public:
   //! Reset currently loaded curve (undone Load()).
   Standard_EXPORT void Reset();
 
-  //! Sets  the Curve <me>  to acces to the  geometry of
+  //! Sets  the Curve <me>  to access the  geometry of
   //! edge <E>.
   Standard_EXPORT void Initialize (const TopoDS_Edge& E);
   
-  //! Sets the Curve <me>  to acces to  the  geometry of
+  //! Sets the Curve <me>  to access  the  geometry of
   //! edge <E>.  The geometry will be computed using the
   //! parametric curve of <E>  on the face <F>. An Error
   //! is raised if the edge  does not  have a pcurve  on
diff --git a/src/BRepAlgo/BRepAlgo_FaceRestrictor.hxx b/src/BRepAlgo/BRepAlgo_FaceRestrictor.hxx
index 5aa1fcb7d8..5d95c34022 100644
--- a/src/BRepAlgo/BRepAlgo_FaceRestrictor.hxx
+++ b/src/BRepAlgo/BRepAlgo_FaceRestrictor.hxx
@@ -44,7 +44,7 @@ public:
   
   Standard_EXPORT BRepAlgo_FaceRestrictor();
   
-  //! the surface of <F> will be the the surface of each new
+  //! the surface of <F> will be the surface of each new
   //! faces built.
   //! <Proj> is used to update pcurves on edges if necessary.
   //! See Add().
diff --git a/src/BRepBlend/BRepBlend_AppFuncRoot.cxx b/src/BRepBlend/BRepBlend_AppFuncRoot.cxx
index 46c703d882..a81ca86e20 100644
--- a/src/BRepBlend/BRepBlend_AppFuncRoot.cxx
+++ b/src/BRepBlend/BRepBlend_AppFuncRoot.cxx
@@ -306,7 +306,7 @@ Standard_Boolean BRepBlend_AppFuncRoot::SearchPoint(Blend_AppFunction& Func,
     Vec(XInit,Pnt);
   }
   else {
-    //  (1.d) Intialisation by linear interpolation
+    //  (1.d) Initialisation by linear interpolation
     Pnt = myLine->Point(Index);
     Vec(X1,Pnt);
     t1 = Pnt.Parameter();
diff --git a/src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx b/src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx
index 72c312232d..cb11204ff1 100644
--- a/src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx
+++ b/src/BRepBuilderAPI/BRepBuilderAPI_Sewing.cxx
@@ -3195,7 +3195,7 @@ void BRepBuilderAPI_Sewing::Merging(const Standard_Boolean /* firstTime */,
                                          MergedWithBound.Contains(iedge));
           if (!isRejected) {
             if (myBoundSections.IsBound(iedge)) {
-              // Edge is splitted - check sections
+              // Edge is split - check sections
               TopTools_ListIteratorOfListOfShape lit(myBoundSections(iedge));
               for (; lit.More() && !isRejected; lit.Next()) {
                 const TopoDS_Shape& sec = lit.Value();
@@ -3289,7 +3289,7 @@ void BRepBuilderAPI_Sewing::Merging(const Standard_Boolean /* firstTime */,
                                            MergedWithSections.Contains(iedge));
             if (!isRejected) {
               if (myBoundSections.IsBound(iedge)) {
-                // Edge is splitted - check sections
+                // Edge is split - check sections
                 TopTools_ListIteratorOfListOfShape lit(myBoundSections(iedge));
                 for (; lit.More() && !isRejected; lit.Next()) {
                   const TopoDS_Shape& sec = lit.Value();
@@ -3370,7 +3370,7 @@ void BRepBuilderAPI_Sewing::Merging(const Standard_Boolean /* firstTime */,
     if (!isMerged && !isMergedSplit) {
       // Nothing was merged in this iteration
       if (isPrevSplit) {
-        // Replace previously splitted bound
+        // Replace previously split bound
         myReShape->Replace(myReShape->Apply(bound),myReShape->Apply(BoundWire));
       }
       //      else if (hasCuttingSections) {
@@ -3726,7 +3726,7 @@ void BRepBuilderAPI_Sewing::Cutting(const Message_ProgressRange& theProgress)
         // Store bound for section
         mySectionBound.Bind(section,bound);
       }
-      // Store splitted bound
+      // Store split bound
       myBoundSections.Bind(bound,listSections);
     }
   }
diff --git a/src/BRepFill/BRepFill_PipeShell.hxx b/src/BRepFill/BRepFill_PipeShell.hxx
index 0d92fae076..08b2e5adfa 100644
--- a/src/BRepFill/BRepFill_PipeShell.hxx
+++ b/src/BRepFill/BRepFill_PipeShell.hxx
@@ -64,7 +64,7 @@ public:
 
   
   //! Set an sweep's mode
-  //! If no mode are setted, the mode use in MakePipe is used
+  //! If no mode are set, the mode used in MakePipe is used
   Standard_EXPORT BRepFill_PipeShell(const TopoDS_Wire& Spine);
   
   //! Set an Frenet or an CorrectedFrenet trihedron
@@ -86,7 +86,7 @@ public:
   //! Set support to the spine to define the BiNormal
   //! at   the spine, like    the  normal the surfaces.
   //! Warning: To  be  effective,  Each  edge  of  the  <spine>  must
-  //! have an  representaion  on   one   face  of<SpineSupport>
+  //! have an  representation  on   one   face  of<SpineSupport>
   Standard_EXPORT Standard_Boolean Set (const TopoDS_Shape& SpineSupport);
   
   //! Set  an  auxiliary  spine  to  define  the Normal
diff --git a/src/BRepMAT2d/BRepMAT2d_Explorer.hxx b/src/BRepMAT2d/BRepMAT2d_Explorer.hxx
index 9fc4d3e81c..9847cd640a 100644
--- a/src/BRepMAT2d/BRepMAT2d_Explorer.hxx
+++ b/src/BRepMAT2d/BRepMAT2d_Explorer.hxx
@@ -96,7 +96,7 @@ protected:
 private:
 
   
-  //! Construction from a set of cuves from Geom2d.
+  //! Construction from a set of curves from Geom2d.
   //! Assume  the   orientation  of  the  closed   lines are
   //! compatible. (ie if A is in B, the orientation of A and B
   //! has to be different.
diff --git a/src/BRepMesh/BRepMesh_Triangulator.hxx b/src/BRepMesh/BRepMesh_Triangulator.hxx
index b1538c4e24..5c3f09d9e3 100644
--- a/src/BRepMesh/BRepMesh_Triangulator.hxx
+++ b/src/BRepMesh/BRepMesh_Triangulator.hxx
@@ -51,7 +51,7 @@ public:
     const NCollection_List<TColStd_SequenceOfInteger>& theWires,
     const gp_Dir&                                      theNorm);
 
-  //! Performs triangulation of source wires and stores triangles the the output list.
+  //! Performs triangulation of source wires and stores triangles the output list.
   Standard_EXPORT Standard_Boolean Perform (NCollection_List<Poly_Triangle>& thePolyTriangles);
 
   //! Set messenger for output information
diff --git a/src/BRepOffsetAPI/BRepOffsetAPI_MakePipeShell.hxx b/src/BRepOffsetAPI/BRepOffsetAPI_MakePipeShell.hxx
index 18e6c56212..c3a56e4103 100644
--- a/src/BRepOffsetAPI/BRepOffsetAPI_MakePipeShell.hxx
+++ b/src/BRepOffsetAPI/BRepOffsetAPI_MakePipeShell.hxx
@@ -67,7 +67,7 @@ public:
   
   //! Constructs the shell-generating framework defined by the wire Spine.
   //! Sets an sweep's mode
-  //! If no mode are setted, the mode use in MakePipe is used
+  //! If no mode are set, the mode use in MakePipe is used
   Standard_EXPORT BRepOffsetAPI_MakePipeShell(const TopoDS_Wire& Spine);
   
   //! Sets a Frenet or a CorrectedFrenet trihedron
@@ -91,7 +91,7 @@ public:
   //! Sets support to the spine to define the BiNormal of
   //! the trihedron, like the normal  to the surfaces.
   //! Warning:  To be effective, Each  edge of the <spine> must
-  //! have an representaion on one face of<SpineSupport>
+  //! have a representation on one face of<SpineSupport>
   Standard_EXPORT Standard_Boolean SetMode (const TopoDS_Shape& SpineSupport);
   
   //! Sets  an  auxiliary  spine  to  define  the Normal
diff --git a/src/BRepOffsetAPI/BRepOffsetAPI_NormalProjection.hxx b/src/BRepOffsetAPI/BRepOffsetAPI_NormalProjection.hxx
index 91415d6a0a..2156812b9c 100644
--- a/src/BRepOffsetAPI/BRepOffsetAPI_NormalProjection.hxx
+++ b/src/BRepOffsetAPI/BRepOffsetAPI_NormalProjection.hxx
@@ -111,7 +111,7 @@ public:
   //! Returns the initial face corresponding to the projected edge E.
   //! Exceptions
   //! StdFail_NotDone if no face was found.
-  //! Standard_NoSuchObject if if a face corresponding to
+  //! Standard_NoSuchObject if a face corresponding to
   //! E has already been found.
   Standard_EXPORT const TopoDS_Shape& Couple (const TopoDS_Edge& E) const;
   
diff --git a/src/BRepTools/BRepTools_Quilt.cxx b/src/BRepTools/BRepTools_Quilt.cxx
index 416ec22a45..f31c864840 100644
--- a/src/BRepTools/BRepTools_Quilt.cxx
+++ b/src/BRepTools/BRepTools_Quilt.cxx
@@ -367,7 +367,7 @@ TopoDS_Shape BRepTools_Quilt::Shells() const
   // - Add the face to an existing shell
   // - Connect other shells if the face touch more than one shell
 
-  // In the Map M the Shell is bound withe the relative orientation of E 
+  // In the Map M the Shell is bound with the relative orientation of E 
   // in the shell
   // In the map MF we binb the face to its shell.
   // In the Map MF the Shell is bound with the relative orientation of F 
diff --git a/src/BSplCLib/BSplCLib.hxx b/src/BSplCLib/BSplCLib.hxx
index 7d89644306..d3947e1dd7 100644
--- a/src/BSplCLib/BSplCLib.hxx
+++ b/src/BSplCLib/BSplCLib.hxx
@@ -663,7 +663,7 @@ public:
   //! * Knots  and multiplicities or "flat knots" without
   //! multiplicities.
   //!
-  //! * The  <Index>  is   the the  localization  of  the
+  //! * The  <Index>  is   the localization  of  the
   //! parameter in the knot sequence.  If <Index> is  out
   //! of range the correct value will be searched.
   //!
@@ -1359,7 +1359,7 @@ public:
   //! FlatKnots are the knots of the BSpline  Starting Condition if =
   //! -1 means the starting point of the curve can move
   //! = 0 means the
-  //! starting  point  of the cuve  cannot  move but  tangen  starting
+  //! starting  point  of the curve  cannot  move but  tangent  starting
   //! point of the curve cannot move
   //! = 1 means the starting point and tangents cannot move
   //! = 2 means the starting point tangent and curvature cannot move
@@ -1386,7 +1386,7 @@ public:
   //! FlatKnots are the knots of the BSpline  Starting Condition if =
   //! -1 means the starting point of the curve can move
   //! = 0 means the
-  //! starting  point  of the cuve  cannot  move but  tangen  starting
+  //! starting  point  of the curve  cannot  move but  tangent  starting
   //! point of the curve cannot move
   //! = 1 means the starting point and tangents cannot move
   //! = 2 means the starting point tangent and curvature cannot move
@@ -1413,7 +1413,7 @@ public:
   //! FlatKnots are the knots of the BSpline  Starting Condition if =
   //! -1 means the starting point of the curve can move
   //! = 0 means the
-  //! starting  point  of the cuve  cannot  move but  tangen  starting
+  //! starting  point  of the curve  cannot  move but  tangent  starting
   //! point of the curve cannot move
   //! = 1 means the starting point and tangents cannot move
   //! = 2 means the starting point tangent and curvature cannot move
diff --git a/src/BVH/BVH_QueueBuilder.hxx b/src/BVH/BVH_QueueBuilder.hxx
index 51d79615dc..7fde18d257 100644
--- a/src/BVH/BVH_QueueBuilder.hxx
+++ b/src/BVH/BVH_QueueBuilder.hxx
@@ -164,7 +164,7 @@ protected:
                                                                      BVH_Tree<T, N>*        theBVH,
                                                                      const Standard_Integer theNode) const = 0;
 
-  //! Processes child nodes of the splitted BVH node.
+  //! Processes child nodes of the split BVH node.
   virtual void addChildren (BVH_Tree<T, N>*        theBVH,
                             BVH_BuildQueue&        theBuildQueue,
 							const Standard_Integer theNode,
diff --git a/src/Bisector/Bisector_Bisec.cxx b/src/Bisector/Bisector_Bisec.cxx
index cb63dc7683..7159fc6936 100644
--- a/src/Bisector/Bisector_Bisec.cxx
+++ b/src/Bisector/Bisector_Bisec.cxx
@@ -70,7 +70,7 @@ Bisector_Bisec::Bisector_Bisec()
 //   apoint        :   point through which the bissectrice should pass.         
 //   afirstvector  : \ vectors to determine the sector where       
 //   asecondvector : / the bissectrice should be located.                      
-//   adirection    :   shows the the side of the bissectrice to be preserved.       
+//   adirection    :   shows the side of the bissectrice to be preserved.
 //   tolerance     :   threshold starting from which the bisectrices are degenerated
 //===========================================================================
 
diff --git a/src/ChFi2d/ChFi2d_Builder.cxx b/src/ChFi2d/ChFi2d_Builder.cxx
index 8cfc9cf394..0e797fe32f 100644
--- a/src/ChFi2d/ChFi2d_Builder.cxx
+++ b/src/ChFi2d/ChFi2d_Builder.cxx
@@ -810,7 +810,7 @@ TopoDS_Edge ChFi2d_Builder::BuildFilletEdge(const TopoDS_Vertex& V,
     Handle(Geom2d_Circle) CC2 = Handle(Geom2d_Circle)::DownCast(basisC2);
     ElCLib::D1(param3,CC2->Circ2d(),p,Ve2);
     Sens2 = (CC2->Circ2d()).IsDirect(); 
-  } // if if (C2->DynamicType() ...
+  } // if (C2->DynamicType() ...
   else {
     Handle(Geom2d_Line) CC2 = Handle(Geom2d_Line)::DownCast(basisC2);
     ElCLib::D1(param3,CC2->Lin2d(),p,Ve2);
diff --git a/src/ChFi3d/ChFi3d_Builder_SpKP.cxx b/src/ChFi3d/ChFi3d_Builder_SpKP.cxx
index 06a4f585af..a1a04de26c 100644
--- a/src/ChFi3d/ChFi3d_Builder_SpKP.cxx
+++ b/src/ChFi3d/ChFi3d_Builder_SpKP.cxx
@@ -672,7 +672,7 @@ Standard_Boolean ChFi3d_Builder::SplitKPart
    Standard_Boolean&                intf,
    Standard_Boolean&                intl)
 {
-  //The the hatching of each faces is started by tangency lines.
+  //The hatching of each faces is started by tangency lines.
   
   Standard_Real pitol = Precision::PIntersection();
   
diff --git a/src/D3DHost/D3DHost_FrameBuffer.cxx b/src/D3DHost/D3DHost_FrameBuffer.cxx
index 6c2b96ebbf..25e4afb877 100644
--- a/src/D3DHost/D3DHost_FrameBuffer.cxx
+++ b/src/D3DHost/D3DHost_FrameBuffer.cxx
@@ -331,7 +331,7 @@ void D3DHost_FrameBuffer::BindBuffer (const Handle(OpenGl_Context)& theCtx)
       myDepthFormat = 0;
       myDepthStencilTexture->Release (theCtx.get());
       theCtx->PushMessage (GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_PORTABILITY, 0, GL_DEBUG_SEVERITY_HIGH,
-                           "D3DHost_FrameBuffer, OpenGL FBO is created without Depth+Stencil attachements!");
+                           "D3DHost_FrameBuffer, OpenGL FBO is created without Depth+Stencil attachments!");
     }
   }
 }
diff --git a/src/DBRep/DBRep.cxx b/src/DBRep/DBRep.cxx
index 973a762203..bb3ed45499 100644
--- a/src/DBRep/DBRep.cxx
+++ b/src/DBRep/DBRep.cxx
@@ -1634,7 +1634,7 @@ void  DBRep::BasicCommands(Draw_Interpretor& theCommands)
   theCommands.Add("numshapes","numshapes s; size of shape",__FILE__,numshapes,g);
   theCommands.Add("countshapes","countshapes s; count of shape",__FILE__,countshapes,g);
   theCommands.Add("setflags",
-                  "setflags shape_name flag1[flag2...]\n sets flags for shape(free, modidfied, checked, orientable, closed, infinite, convex, locked), for exmple <setflags a free> or <setflags a -free> if necessary unflag ",
+                  "setflags shape_name flag1[flag2...]\n sets flags for shape(free, modified, checked, orientable, closed, infinite, convex, locked), for example <setflags a free> or <setflags a -free> if necessary unflag ",
                   __FILE__,setFlags,g);
 
 //  theCommands.Add("dumpmmgt",
diff --git a/src/DDF/DDF.hxx b/src/DDF/DDF.hxx
index 6b3db337b0..71a22ea186 100644
--- a/src/DDF/DDF.hxx
+++ b/src/DDF/DDF.hxx
@@ -43,12 +43,12 @@ public:
   
   //! Search in draw  directory the framewok  identified
   //! by its name <Name>. returns True if found. In that
-  //! case <DF> is setted.
+  //! case <DF> is set.
   Standard_EXPORT static Standard_Boolean GetDF (Standard_CString& Name, Handle(TDF_Data)& DF, const Standard_Boolean Complain = Standard_True);
   
   //! Search in <DF>  the label identified by its  entry
   //! <Entry>.  returns  <True> if  found. In  that case
-  //! <Label> is setted.
+  //! <Label> is set.
   Standard_EXPORT static Standard_Boolean FindLabel (const Handle(TDF_Data)& DF, const Standard_CString Entry, TDF_Label& Label, const Standard_Boolean Complain = Standard_True);
   
   //! Search in <DF> the  label identified by its entry
@@ -58,7 +58,7 @@ public:
   
   //! Search   in <DF> the  attribute  identified by its
   //! <ID> and its <entry>.  returns <True> if found. In
-  //! that case A is setted.
+  //! that case A is set.
   Standard_EXPORT static Standard_Boolean Find (const Handle(TDF_Data)& DF, const Standard_CString Entry, const Standard_GUID& ID, Handle(TDF_Attribute)& A, const Standard_Boolean Complain = Standard_True);
   
   //! Safe variant for arbitrary type of argument
diff --git a/src/DDF/DDF_Browser.hxx b/src/DDF/DDF_Browser.hxx
index 4b61c31705..0b519a6f39 100644
--- a/src/DDF/DDF_Browser.hxx
+++ b/src/DDF/DDF_Browser.hxx
@@ -69,7 +69,7 @@ public:
   
   //! Returns a string composed with the list of
   //! referenced attribute index of the attribute
-  //! <anIndex>. For exemple, it is usefull for
+  //! <anIndex>. For example, it is useful for
   //! TDataStd_Group. It uses a mechanism based on a
   //! DDF_AttributeBrowser.
   Standard_EXPORT TCollection_AsciiString OpenAttribute (const Standard_Integer anIndex = 0);
diff --git a/src/DDF/DDF_DataCommands.cxx b/src/DDF/DDF_DataCommands.cxx
index f0e4391e02..53117d9387 100644
--- a/src/DDF/DDF_DataCommands.cxx
+++ b/src/DDF/DDF_DataCommands.cxx
@@ -257,7 +257,7 @@ static Standard_Integer CopyLabel_SCopy (Draw_Interpretor& di,Standard_Integer n
     if(!DDF::GetDF(a[1], DF)) return 1;
     if (!DDF::FindLabel(DF,a[2],SOURCE)) return 1;   
     if (DDF::FindLabel(DF,a[3],TARGET)) {
-      di << " target label is already setted \n";
+      di << " target label is already set \n";
       return 1;
     }
     DDF::AddLabel(DF,a[3],TARGET);
diff --git a/src/DDataStd/DDataStd_BasicCommands.cxx b/src/DDataStd/DDataStd_BasicCommands.cxx
index 0d7b16d664..3cc31d1017 100644
--- a/src/DDataStd/DDataStd_BasicCommands.cxx
+++ b/src/DDataStd/DDataStd_BasicCommands.cxx
@@ -367,7 +367,7 @@ static Standard_Integer DDataStd_Self (Draw_Interpretor& di,
     TDF_Label L;
     if (!DDF::FindLabel(DF,arg[2],L)) return 1; 
 //    TDataStd::MakeSelfContained(L,removed);
-//    if (removed.IsEmpty()) std::cout << "noone attriburte removed" << std::endl;
+//    if (removed.IsEmpty()) std::cout << "no attribute removed" << std::endl;
 //    for (TDF_ListIteratorOfAttributeList it(removed);it.More();it.Next()) {
 //      TDF_Tool::Entry(it.Value()->Label(),s); std::cout  << s << " ";
 //      std::cout << std::endl;
diff --git a/src/DDataStd/DDataStd_DrawPresentation.hxx b/src/DDataStd/DDataStd_DrawPresentation.hxx
index 034934f266..694d264a11 100644
--- a/src/DDataStd/DDataStd_DrawPresentation.hxx
+++ b/src/DDataStd/DDataStd_DrawPresentation.hxx
@@ -33,7 +33,7 @@ class TDF_AttributeDelta;
 class DDataStd_DrawPresentation;
 DEFINE_STANDARD_HANDLE(DDataStd_DrawPresentation, TDF_Attribute)
 
-//! draw presentaion of a label of a document
+//! draw presentation of a label of a document
 class DDataStd_DrawPresentation : public TDF_Attribute
 {
 
diff --git a/src/DDataStd/DDataStd_TreeBrowser.tcl b/src/DDataStd/DDataStd_TreeBrowser.tcl
index fdca7468b4..3c17aaff86 100644
--- a/src/DDataStd/DDataStd_TreeBrowser.tcl
+++ b/src/DDataStd/DDataStd_TreeBrowser.tcl
@@ -26,7 +26,7 @@
 # white     : interoperable
 # white + c : non interoperable
 # X         : X Reference
-# Red       : not yet commited in transaction #0
+# Red       : not yet committed in transaction #0
 # 
 #
 
@@ -157,7 +157,7 @@ proc TREE:Tree:InitTextPanel { TreeBrowser w p } {
 
     $TREE_WINDOWS($w,NAV,text) insert end " Welcome to the QDF browser (Rev #.#)\n"
     $TREE_WINDOWS($w,NAV,text) insert end "--------------------------------------\n\n"
-    $TREE_WINDOWS($w,NAV,text) insert end "This browser is an easy to use prototype made with Tix technology. We hope it will be usefull for understanding and debugging QDF.\n"
+    $TREE_WINDOWS($w,NAV,text) insert end "This browser is an easy to use prototype made with Tix technology. We hope it will be useful for understanding and debugging QDF.\n"
     $TREE_WINDOWS($w,NAV,text) insert end "\t\t\t\tFID & YAN"
 }
 
diff --git a/src/DDocStd/DDocStd_ShapeSchemaCommands.cxx b/src/DDocStd/DDocStd_ShapeSchemaCommands.cxx
index b18462bc8e..438764a1aa 100644
--- a/src/DDocStd/DDocStd_ShapeSchemaCommands.cxx
+++ b/src/DDocStd/DDocStd_ShapeSchemaCommands.cxx
@@ -61,7 +61,7 @@ static void DDocStd_StorageErrorMessage (Draw_Interpretor& theDI, const Storage_
     theDI << "Storage error: error during writing";
     break;
   case Storage_VSFormatError:
-    theDI << "Storage error: wrong format error occured while reading";
+    theDI << "Storage error: wrong format error occurred while reading";
     break;
   case Storage_VSUnknownType:
     theDI << "Storage error: try to read an unknown type";
diff --git a/src/DNaming/DNaming.cxx b/src/DNaming/DNaming.cxx
index 9fca99f3b8..b0705f238f 100644
--- a/src/DNaming/DNaming.cxx
+++ b/src/DNaming/DNaming.cxx
@@ -273,7 +273,7 @@ static void LoadC0Edges(const TopoDS_Shape& S,
   }
   
   TopTools_MapOfShape anEdgesToDelete;
-  TopExp_Explorer anEx(S,TopAbs_EDGE); // mpv: new explorer iterator becouse we need keep edges order
+  TopExp_Explorer anEx(S,TopAbs_EDGE); // mpv: new explorer iterator because we need keep edges order
   for(;anEx.More();anEx.Next()) {
     Standard_Boolean aC0 = Standard_False;
     TopoDS_Shape anEdge1 = anEx.Current();
@@ -602,7 +602,7 @@ Handle(TNaming_NamedShape) DNaming::GetObjectValue(const Handle(TDataStd_UAttrib
 
 //=======================================================================
 //function : GetPrevFunction
-//purpose  : Returns previus function
+//purpose  : Returns previous function
 //=======================================================================
 Handle(TFunction_Function) DNaming::GetPrevFunction(const Handle(TFunction_Function)& theFunction)
 {
diff --git a/src/DNaming/DNaming_BasicCommands.cxx b/src/DNaming/DNaming_BasicCommands.cxx
index 4a2ca3107b..c07759e240 100644
--- a/src/DNaming/DNaming_BasicCommands.cxx
+++ b/src/DNaming/DNaming_BasicCommands.cxx
@@ -156,7 +156,7 @@ static Standard_Integer Getentry (Draw_Interpretor& di, Standard_Integer n, cons
 
   TopoDS_Shape S = DBRep::Get(a[2]);
   if (S.IsNull()) {
-    di <<"Noone shape selected\n";
+    di <<"No shape selected\n";
     //di << 0;
     return 0;
   }
@@ -176,7 +176,7 @@ static Standard_Integer Getentry (Draw_Interpretor& di, Standard_Integer n, cons
 
 //=======================================================================
 //function : NamedShape
-//purpose  : retrive label of Primitive or a Generated shape
+//purpose  : retrieve label of Primitive or a Generated shape
 //=======================================================================
 static Standard_Integer NamedShape(Draw_Interpretor& di, Standard_Integer n, const char** a)
 {
@@ -187,7 +187,7 @@ static Standard_Integer NamedShape(Draw_Interpretor& di, Standard_Integer n, con
   if (!DDF::GetDF(a[1],ND)) return 1;
   TopoDS_Shape  SS = DBRep::Get(a[2]);
   if (SS.IsNull()) {
-    di <<"Noone shape selected\n";
+    di <<"No shape selected\n";
     //di << 0;
     return 0;
   }
@@ -396,7 +396,7 @@ static Standard_Integer Collect (Draw_Interpretor& di,
 }
 //=======================================================================
 //function : GetCreationEntry
-//purpose  : retrive label of Primitive or a Generated shape
+//purpose  : retrieve label of Primitive or a Generated shape
 //=======================================================================
 static Standard_Integer Getcreationentry (Draw_Interpretor& di, Standard_Integer n, const char** a)
 {
@@ -410,7 +410,7 @@ static Standard_Integer Getcreationentry (Draw_Interpretor& di, Standard_Integer
   TopoDS_Shape  SS = DBRep::Get(a[2]);
 
   if (SS.IsNull()) {
-    di <<"Noone shape selected\n";
+    di <<"No shape selected\n";
     //di << 0;
     return 0;
   }
diff --git a/src/DNaming/DNaming_ModelingCommands.cxx b/src/DNaming/DNaming_ModelingCommands.cxx
index 01e1177cdd..a8e442a677 100644
--- a/src/DNaming/DNaming_ModelingCommands.cxx
+++ b/src/DNaming/DNaming_ModelingCommands.cxx
@@ -712,7 +712,7 @@ static Standard_Integer DNaming_AttachShape (Draw_Interpretor& di,
 	    Handle(TFunction_Function) aCntFun;
 	    if(aCont->Label().Father().FindAttribute(TFunction_Function::GetID(), aCntFun)) { //Fun:2 ==> result
 	      // First argument of Selection function refers to father function (of context object) 
-	      // to which selection is attached (because sel obj. itself already has refrence to result NS
+	      // to which selection is attached (because sel obj. itself already has reference to result NS
 	      TDF_Reference::Set(aFun->Label().FindChild(FUNCTION_ARGUMENTS_LABEL).FindChild(ATTACH_ARG), 
 				 aCntFun->Label()); //ref to function produced Context shape
 	      
@@ -1714,7 +1714,7 @@ static Standard_Boolean MakeSelection (const Handle(TDataStd_UAttribute)& Obj,
 	  Handle(TFunction_Function) aCntFun;
 	  if(aNS->Label().Father().FindAttribute(TFunction_Function::GetID(), aCntFun)) { //Fun:2 ==> result
 	      // First argument of Selection function refers to father function (of context object) 
-	      // to which selection is attached (because sel obj. itself already has refrence to result NS
+	      // to which selection is attached (because sel obj. itself already has reference to result NS
 	    TDF_Reference::Set(aFun->Label().FindChild(FUNCTION_ARGUMENTS_LABEL).FindChild(ATTACH_ARG), 
 			       aCntFun->Label()); //ref to function produced Context shape
 	    
@@ -1772,7 +1772,7 @@ static Standard_Boolean MakeXSelection (const Handle(TDataStd_UAttribute)& Obj,
 	  Handle(TFunction_Function) aCntFun;
 	  if(aNS->Label().Father().FindAttribute(TFunction_Function::GetID(), aCntFun)) { //Fun:2 ==> result
 	      // First argument of Selection function refers to father function (of context object) 
-	      // to which selection is attached (because sel obj. itself already has refrence to result NS
+	      // to which selection is attached (because sel obj. itself already has reference to result NS
 	    TDF_Reference::Set(aFun->Label().FindChild(FUNCTION_ARGUMENTS_LABEL).FindChild(ATTACH_ARG), 
 			       aCntFun->Label()); //ref to function produced Context shape
 	    
diff --git a/src/DPrsStd/DPrsStd_AISPresentationCommands.cxx b/src/DPrsStd/DPrsStd_AISPresentationCommands.cxx
index 0ae5914550..1a4c02f3b0 100644
--- a/src/DPrsStd/DPrsStd_AISPresentationCommands.cxx
+++ b/src/DPrsStd/DPrsStd_AISPresentationCommands.cxx
@@ -167,7 +167,7 @@ static Standard_Integer DPrsStd_AISSet (Draw_Interpretor& di,
     Standard_GUID guid;
     TCollection_ExtendedString str = arg[3];
 #ifdef OCCT_DEBUG
-    std::cout << "Inputed parameter > " << str   << std::endl;
+    std::cout << "Inputted parameter > " << str   << std::endl;
 #endif
     if ( str == "A" )  //axis
       guid = TDataXtd_Axis::GetID();     //"2a96b601-ec8b-11d0-bee7-080009dc3333" 
@@ -233,7 +233,7 @@ static Standard_Integer DPrsStd_AISDriver (Draw_Interpretor& di,
       else {
 	TCollection_ExtendedString str = arg[3];
 #ifdef OCCT_DEBUG
-	std::cout << "Inputed parameter > " << str   << std::endl;
+	std::cout << "Inputted parameter > " << str   << std::endl;
 #endif
 	if ( str == "A" )  //axis
 	  guid = TDataXtd_Axis::GetID();     //"2a96b601-ec8b-11d0-bee7-080009dc3333" 
diff --git a/src/Draft/Draft_Modification.hxx b/src/Draft/Draft_Modification.hxx
index 32bec2e51f..4550da76dd 100644
--- a/src/Draft/Draft_Modification.hxx
+++ b/src/Draft/Draft_Modification.hxx
@@ -95,7 +95,7 @@ public:
   Standard_EXPORT Draft_ErrorStatus Error() const;
   
   //! Returns the shape (Face,  Edge or Vertex) on which
-  //! an error occured.
+  //! an error occurred.
   Standard_EXPORT const TopoDS_Shape& ProblematicShape() const;
   
   //! Returns all  the  faces   which  have been   added
@@ -145,7 +145,7 @@ public:
   //! <Tol> are not significant.
   //!
   //! <NewE> is the new  edge created from  <E>.  <NewF>
-  //! is the new face created from <F>. They may be usefull.
+  //! is the new face created from <F>. They may be useful.
   Standard_EXPORT Standard_Boolean NewCurve2d (const TopoDS_Edge& E, const TopoDS_Face& F, const TopoDS_Edge& NewE, const TopoDS_Face& NewF, Handle(Geom2d_Curve)& C, Standard_Real& Tol) Standard_OVERRIDE;
   
   //! Returns Standard_True if the Vertex  <V> has a new
diff --git a/src/Draw/Draw.hxx b/src/Draw/Draw.hxx
index 87317b338d..e8cbffe4ff 100644
--- a/src/Draw/Draw.hxx
+++ b/src/Draw/Draw.hxx
@@ -75,7 +75,7 @@ public: //! @name Tcl variables management tools
   //! variable exist.
   Standard_EXPORT static Standard_Boolean Get (const Standard_CString Name, Standard_Real& val);
   
-  //! Sets a TCL sting variable
+  //! Sets a TCL string variable
   Standard_EXPORT static void Set (const Standard_CString Name, const Standard_CString val);
 
 public: //! @name argument parsing tools
diff --git a/src/Draw/Draw_BasicCommands.cxx b/src/Draw/Draw_BasicCommands.cxx
index 7d6b37e66a..0270aaf7a0 100644
--- a/src/Draw/Draw_BasicCommands.cxx
+++ b/src/Draw/Draw_BasicCommands.cxx
@@ -87,7 +87,7 @@ static Standard_Integer chronom(Draw_Interpretor& di,
       Draw_Chrono = (*a[1] == '1');
 
     if (Draw_Chrono) di << "Chronometers activated.\n";
-    else di << "Chronometers desactivated.\n";
+    else di << "Chronometers deactivated.\n";
   }
   else {
     Handle(Draw_Drawable3D) D = Draw::Get(a[1]);
@@ -155,7 +155,7 @@ static Standard_Integer dchronom(Draw_Interpretor& theDI,
       Draw_Chrono = (*a[1] == '1');
 
     if (Draw_Chrono) theDI << "Chronometers activated.\n";
-    else theDI << "Chronometers desactivated.\n";
+    else theDI << "Chronometers deactivated.\n";
   }
   else {
     Handle(Draw_Drawable3D) D = Draw::Get(a[1]);
diff --git a/src/Draw/Draw_Display.hxx b/src/Draw/Draw_Display.hxx
index b2d9dcd947..7fe68ac8b9 100644
--- a/src/Draw/Draw_Display.hxx
+++ b/src/Draw/Draw_Display.hxx
@@ -110,7 +110,7 @@ public:
   //! display is drawing.
   Standard_EXPORT Standard_Integer ViewId() const;
   
-  //! Returs  True  if  the  last   drawing   operations
+  //! Returns  True  if  the  last   drawing   operations
   //! generated  a pick hit.  When HasPicked is True the
   //! Drawing should be resumed.
   //!
diff --git a/src/Draw/Draw_Drawable3D.hxx b/src/Draw/Draw_Drawable3D.hxx
index 8cfa3bd1bb..a89dec176f 100644
--- a/src/Draw/Draw_Drawable3D.hxx
+++ b/src/Draw/Draw_Drawable3D.hxx
@@ -41,7 +41,7 @@ public:
   
   Standard_EXPORT virtual void DrawOn (Draw_Display& dis) const = 0;
   
-  //! Returs True if the pick is outside the box
+  //! Returns True if the pick is outside the box
   Standard_EXPORT virtual Standard_Boolean PickReject (const Standard_Real X, const Standard_Real Y, const Standard_Real Prec) const;
   
   //! For variable copy.
diff --git a/src/Draw/Draw_Main.hxx b/src/Draw/Draw_Main.hxx
index 81e742df36..2ccb4839f2 100644
--- a/src/Draw/Draw_Main.hxx
+++ b/src/Draw/Draw_Main.hxx
@@ -15,7 +15,7 @@
 // commercial license or contractual agreement.
 
 // Defines common framework for declaration of main/WinMain functions 
-// for executbales on UNIX and WNT that extends DRAW Test Harness.
+// for executables on UNIX and WNT that extends DRAW Test Harness.
 
 // In order to create executable in DRAW environment, in the executable
 // the following line should be added:
diff --git a/src/Draw/Draw_Marker2D.hxx b/src/Draw/Draw_Marker2D.hxx
index 62009d6a00..7b65901433 100644
--- a/src/Draw/Draw_Marker2D.hxx
+++ b/src/Draw/Draw_Marker2D.hxx
@@ -51,7 +51,7 @@ public:
   
   Standard_EXPORT void DrawOn (Draw_Display& dis) const Standard_OVERRIDE;
   
-  //! Returs always false
+  //! Returns always false
   Standard_EXPORT virtual Standard_Boolean PickReject (const Standard_Real X, const Standard_Real Y, const Standard_Real Prec) const Standard_OVERRIDE;
 
 
diff --git a/src/Draw/Draw_Marker3D.hxx b/src/Draw/Draw_Marker3D.hxx
index 7645f951fb..255609bc79 100644
--- a/src/Draw/Draw_Marker3D.hxx
+++ b/src/Draw/Draw_Marker3D.hxx
@@ -51,7 +51,7 @@ public:
   
   Standard_EXPORT void DrawOn (Draw_Display& dis) const Standard_OVERRIDE;
   
-  //! Returs always false
+  //! Returns always false
   Standard_EXPORT virtual Standard_Boolean PickReject (const Standard_Real X, const Standard_Real Y, const Standard_Real Prec) const Standard_OVERRIDE;
 
 
diff --git a/src/Draw/Draw_Number.hxx b/src/Draw/Draw_Number.hxx
index bb3a116841..162f0a2c6f 100644
--- a/src/Draw/Draw_Number.hxx
+++ b/src/Draw/Draw_Number.hxx
@@ -31,7 +31,7 @@ class Draw_Drawable3D;
 class Draw_Number;
 DEFINE_STANDARD_HANDLE(Draw_Number, Draw_Drawable3D)
 
-//! To store nummbers in variables.
+//! To store numbers in variables.
 class Draw_Number : public Draw_Drawable3D
 {
 
diff --git a/src/Draw/Draw_VariableCommands.cxx b/src/Draw/Draw_VariableCommands.cxx
index 771c358cab..01aa8e9a34 100644
--- a/src/Draw/Draw_VariableCommands.cxx
+++ b/src/Draw/Draw_VariableCommands.cxx
@@ -49,7 +49,7 @@ static Standard_Boolean autodisp = Standard_True;
 static Standard_Boolean repaint2d,repaint3d;
 
 //===============================================
-// dictionnary of variables
+// dictionary of variables
 // Variables are stored in a map Integer, Transient
 // The Integer Value is the content of the TCl variable 
 //===============================================
diff --git a/src/Draw/Draw_Window.cxx b/src/Draw/Draw_Window.cxx
index b2ef2d63c7..e2191f23f0 100644
--- a/src/Draw/Draw_Window.cxx
+++ b/src/Draw/Draw_Window.cxx
@@ -933,8 +933,8 @@ void Draw_Window::WUnmapNotify()
 
 
 //======================================================
-// funtion : ProcessEvents
-// purpose : process pending X events
+// function : ProcessEvents
+// purpose  : process pending X events
 //======================================================
 
 static void ProcessEvents(ClientData,int)
@@ -966,7 +966,7 @@ static void ProcessEvents(ClientData,int)
 }
 
 //======================================================
-// funtion : GetNextEvent()
+// function : GetNextEvent()
 // purpose :
 //======================================================
 void GetNextEvent(Event& ev)
@@ -995,7 +995,7 @@ void GetNextEvent(Event& ev)
 #endif //__APPLE__
 
 //======================================================
-// funtion :Run_Appli
+// function :Run_Appli
 // purpose :
 //======================================================
 
@@ -1092,8 +1092,8 @@ void Run_Appli(Standard_Boolean (*interprete) (const char*))
 }
 
 //======================================================
-// funtion : Init_Appli()
-// purpose :
+// function : Init_Appli()
+// purpose  :
 //======================================================
 Standard_Boolean Init_Appli()
 {
@@ -1166,8 +1166,8 @@ Standard_Boolean Init_Appli()
 }
 
 //======================================================
-// funtion : Destroy_Appli()
-// purpose :
+// function : Destroy_Appli()
+// purpose  :
 //======================================================
 void Destroy_Appli()
 {
@@ -1343,7 +1343,7 @@ HPEN colorPenTab[MAXCOLOR] = {CreatePen(PS_SOLID, PENWIDTH, RGB(255,255,255)),
                               CreatePen(PS_SOLID, PENWIDTH, RGB(240,230,140)),
                               CreatePen(PS_SOLID, PENWIDTH, RGB(255,127,80))};
 
-// Correspondance mode X11 and WINDOWS NT
+// Correspondence mode X11 and WINDOWS NT
 int modeTab[16] = {R2_BLACK, R2_MASKPEN, R2_MASKPENNOT, R2_COPYPEN,
                    R2_MASKNOTPEN, R2_NOP, R2_XORPEN, R2_MERGEPEN,
                    R2_NOTMASKPEN, R2_NOTXORPEN, R2_NOT, R2_MERGEPENNOT,
diff --git a/src/Draw/Draw_Window.hxx b/src/Draw/Draw_Window.hxx
index 38b49d90f3..7f382fa782 100644
--- a/src/Draw/Draw_Window.hxx
+++ b/src/Draw/Draw_Window.hxx
@@ -73,7 +73,7 @@ class Draw_Window
 
     /**
      * This method registers a callback function that will be called just before exit.
-     * This is usefull especially for Windows platform, on which Draw is normally 
+     * This is useful especially for Windows platform, on which Draw is normally 
      * self-terminated instead of exiting.
      */
     Standard_EXPORT static void AddCallbackBeforeTerminate(FCallbackBeforeTerminate theCB);
@@ -179,7 +179,7 @@ class Draw_Window
 };
 
 //======================================================
-// funtion : Run_Appli
+// function : Run_Appli
 // purpose : run the application
 //           interp will be called to interpret a command
 //           and return True if the command is complete
@@ -188,19 +188,19 @@ class Draw_Window
 void Run_Appli(Standard_Boolean (*inteprete) (const char*));
 
 //======================================================
-// funtion : Init_Appli
+// function : Init_Appli
 // purpose :
 //======================================================
 Standard_Boolean Init_Appli();
 
 //======================================================
-// funtion : Destroy_Appli()
+// function : Destroy_Appli()
 // purpose :
 //======================================================
 void Destroy_Appli();
 
 //======================================================
-// funtion : GetNextEvent()
+// function : GetNextEvent()
 // purpose :
 //======================================================
 void GetNextEvent(Event&);
@@ -247,7 +247,7 @@ class Draw_Window
 
   /**
    * This method registers a callback function that will be called just before exit.
-   * This is usefull especially for Windows platform, on which Draw is normally 
+   * This is useful especially for Windows platform, on which Draw is normally 
    * self-terminated instead of exiting.
    */
   Standard_EXPORT static void AddCallbackBeforeTerminate(FCallbackBeforeTerminate theCB);
@@ -323,7 +323,7 @@ private:
 };
 
 //======================================================
-// funtion : Run_Appli
+// function : Run_Appli
 // purpose : run the application
 //           interp will be called to interpret a command
 //           and return True if the command is complete
@@ -332,19 +332,19 @@ private:
 void Run_Appli(Standard_Boolean (*inteprete) (const char*));
 
 //======================================================
-// funtion : Init_Appli
+// function : Init_Appli
 // purpose :
 //======================================================
 Standard_Boolean Init_Appli();
 
 //======================================================
-// funtion : Destroy_Appli()
+// function : Destroy_Appli()
 // purpose :
 //======================================================
 void Destroy_Appli();
 
 //======================================================
-// funtion : GetNextEvent()
+// function : GetNextEvent()
 // purpose :
 //======================================================
 void GetNextEvent (Standard_Boolean  theWait,
@@ -408,7 +408,7 @@ public:
 
   /**
    * This method registers a callback function that will be called just before exit.
-   * This is usefull especially for Windows platform, on which Draw is normally 
+   * This is useful especially for Windows platform, on which Draw is normally 
    * self-terminated instead of exiting.
    */
   Standard_EXPORT static void AddCallbackBeforeTerminate(FCallbackBeforeTerminate theCB);
diff --git a/src/DrawResources/CheckCommands.tcl b/src/DrawResources/CheckCommands.tcl
index 0faa900342..6f367a3e33 100644
--- a/src/DrawResources/CheckCommands.tcl
+++ b/src/DrawResources/CheckCommands.tcl
@@ -14,7 +14,7 @@
 ############################################################################
 # This file defines scripts for verification of OCCT tests.
 # It provides top-level commands starting with 'check'.
-# Type 'help check*' to get their synopsys.
+# Type 'help check*' to get their synopsis.
 # See OCCT Tests User Guide for description of the test system.
 #
 # Note: procedures with names starting with underscore are for internal use
@@ -211,7 +211,7 @@ help checknbshapes {
         the same sub-shapes with different location as different sub-shapes.
     -m msg: print "msg" in case of error
     -ref [nbshapes a]: compare the number of sub-shapes in "shape" and in "a".
-                       -vertex N, -edge N and other options are stil working.
+                       -vertex N, -edge N and other options are still working.
 }
 proc checknbshapes {shape args} {
   puts "checknbshapes ${shape} ${args}"
@@ -663,7 +663,7 @@ proc checkdump {shape args} {
         }
         foreach item ${local_ref} {
             if { ![regexp "$pattern$number_pattern" $ddump full res] } {
-                puts "Error: cheked parameter ${param} is not listed in dump"
+                puts "Error: checked parameter ${param} is not listed in dump"
                 break
             }
             lappend ref_values $res 
@@ -997,7 +997,7 @@ proc checktrinfo {shape args} {
     # get reference values from -ref option
     if { "${ref_info}" != ""} {
         if {![regexp "${triinfo_pattern}" ${ref_info} dump ref_nb_triangles ref_nb_nodes ref_deflection]} {
-            puts "Error: reference information gived by -ref option is wrong"
+            puts "Error: reference information given by -ref option is wrong"
         }
     }
 
@@ -1050,9 +1050,9 @@ help checkplatform {
 
   Use: checkplatform [options...]
   Allowed options are:
-    -windows : return 1 if current platform is 'Windows', overwise return 0
-    -linux   : return 1 if current platform is 'Linux', overwise return 0
-    -osx     : return 1 if current platform is 'MacOS X', overwise return 0
+    -windows : return 1 if current platform is 'Windows', otherwise return 0
+    -linux   : return 1 if current platform is 'Linux', otherwise return 0
+    -osx     : return 1 if current platform is 'MacOS X', otherwise return 0
 
   Only one option can be used at once.
   If no option is given, procedure will return the name of current platform.
diff --git a/src/DrawResources/TestCommands.tcl b/src/DrawResources/TestCommands.tcl
index 5979b02d5a..3618873058 100644
--- a/src/DrawResources/TestCommands.tcl
+++ b/src/DrawResources/TestCommands.tcl
@@ -15,7 +15,7 @@
 # This file defines scripts for execution of OCCT tests.
 # It should be loaded automatically when DRAW is started, and provides
 # top-level commands starting with 'test'. Type 'help test' to get their
-# synopsys.
+# synopsis.
 # See OCCT Tests User Guide for description of the test system.
 #
 # Note: procedures with names starting with underscore are for internal use 
diff --git a/src/DrawResources/dftree.tcl b/src/DrawResources/dftree.tcl
index 44d0e9e3f1..a7f804b18e 100755
--- a/src/DrawResources/dftree.tcl
+++ b/src/DrawResources/dftree.tcl
@@ -26,7 +26,7 @@
 # white     : interoperable
 # white + c : non interoperable
 # X         : X Reference
-# Red       : not yet commited in transaction #0
+# Red       : not yet committed in transaction #0
 # 
 #
 
diff --git a/src/DrawTrSurf/DrawTrSurf.cxx b/src/DrawTrSurf/DrawTrSurf.cxx
index feb6d5f5da..97bd566af9 100644
--- a/src/DrawTrSurf/DrawTrSurf.cxx
+++ b/src/DrawTrSurf/DrawTrSurf.cxx
@@ -1362,7 +1362,7 @@ void  DrawTrSurf::BasicCommands(Draw_Interpretor& theCommands)
  marker of the point\n\n").Cat(MarkersHint).ToCString(),
   		  __FILE__,changepointmarker,g);
 
-  g = "Geometric tranformations";
+  g = "Geometric transformations";
   
   theCommands.Add("translate",
 		  "translate name [names...] dx dy dz",
diff --git a/src/DsgPrs/DsgPrs_AnglePresentation.cxx b/src/DsgPrs/DsgPrs_AnglePresentation.cxx
index e467f3663b..3d2e0dd8aa 100644
--- a/src/DsgPrs/DsgPrs_AnglePresentation.cxx
+++ b/src/DsgPrs/DsgPrs_AnglePresentation.cxx
@@ -95,7 +95,7 @@ void DsgPrs_AnglePresentation::Add (const Handle(Prs3d_Presentation)& aPresentat
   gp_Pnt P1 = ElCLib::Value(0., myCircle);
   gp_Pnt P2 = ElCLib::Value(M_PI, myCircle);
 
-  gce_MakePln mkPln(P1, P2, Apex); // create a plane whitch defines plane for projection aPosition on it
+  gce_MakePln mkPln(P1, P2, Apex); // create a plane which defines plane for projection aPosition on it
 
   gp_Vec aVector( mkPln.Value().Location(), aPosition );     //project aPosition on a plane
   gp_Vec Normal = mkPln.Value().Axis().Direction(); 
@@ -116,7 +116,7 @@ void DsgPrs_AnglePresentation::Add (const Handle(Prs3d_Presentation)& aPresentat
     OppositePnt = P1;
   }
 
-  aPnt = AttachmentPnt ;                          // Creating of circle whitch defines a plane for a dimension arc
+  aPnt = AttachmentPnt ;                          // Creating of circle which defines a plane for a dimension arc
   gp_Vec Vec(AttachmentPnt, Apex);                // Dimension arc is a part of the circle 
   Vec.Scale(2.);
   aPnt.Translate(Vec);
diff --git a/src/DsgPrs/DsgPrs_DatumPrs.hxx b/src/DsgPrs/DsgPrs_DatumPrs.hxx
index 41bbe5469d..23da441058 100644
--- a/src/DsgPrs/DsgPrs_DatumPrs.hxx
+++ b/src/DsgPrs/DsgPrs_DatumPrs.hxx
@@ -27,7 +27,7 @@ public:
   DEFINE_STANDARD_ALLOC
 
   //! Draw XYZ axes at specified location with attributes defined by the attribute manager theDrawer:
-  //! - Prs3d_DatumAspect defines arrow, line and lenght trihedron axis parameters,
+  //! - Prs3d_DatumAspect defines arrow, line and length trihedron axis parameters,
   //! - Prs3d_TextAspect defines displayed text.
   //! The thihedron origin and axis directions are defined by theDatum coordinate system.
   //! DsgPrs_XYZAxisPresentation framework is used to create graphical primitives for each axis.
diff --git a/src/DsgPrs/DsgPrs_FixPresentation.hxx b/src/DsgPrs/DsgPrs_FixPresentation.hxx
index 840a9664a6..09a5772515 100644
--- a/src/DsgPrs/DsgPrs_FixPresentation.hxx
+++ b/src/DsgPrs/DsgPrs_FixPresentation.hxx
@@ -38,7 +38,7 @@ public:
   //! draws the presentation of fixed objects by
   //! drawing the 'fix' symbol at position <aPntEnd>.
   //! A binding segment is drawn between <aPntAttach>
-  //! ( which belongs the the fix object) and <aPntEnd>.
+  //! ( which belongs to the fixed object) and <aPntEnd>.
   //! aSymbSize is the size of the 'fix'symbol
   Standard_EXPORT static void Add (const Handle(Prs3d_Presentation)& aPresentation, const Handle(Prs3d_Drawer)& aDrawer, const gp_Pnt& aPntAttach, const gp_Pnt& aPntEnd, const gp_Dir& aNormPln, const Standard_Real aSymbSize);
 
diff --git a/src/DsgPrs/DsgPrs_OffsetPresentation.hxx b/src/DsgPrs/DsgPrs_OffsetPresentation.hxx
index e141da9294..1ff83b6bb5 100644
--- a/src/DsgPrs/DsgPrs_OffsetPresentation.hxx
+++ b/src/DsgPrs/DsgPrs_OffsetPresentation.hxx
@@ -45,7 +45,7 @@ public:
   //! defined by the attribute manager aDrawer.
   Standard_EXPORT static void Add (const Handle(Prs3d_Presentation)& aPresentation, const Handle(Prs3d_Drawer)& aDrawer, const TCollection_ExtendedString& aText, const gp_Pnt& AttachmentPoint1, const gp_Pnt& AttachmentPoint2, const gp_Dir& aDirection, const gp_Dir& aDirection2, const gp_Pnt& OffsetPoint);
   
-  //! draws the representation of axes alignement Constraint
+  //! draws the representation of axes alignment Constraint
   //! between the point AttachmentPoint1 and the
   //! point AttachmentPoint2, along direction
   //! aDirection, using the offset point OffsetPoint.
diff --git a/src/DsgPrs/DsgPrs_SymmetricPresentation.cxx b/src/DsgPrs/DsgPrs_SymmetricPresentation.cxx
index 8772f9bc41..5c1d860895 100644
--- a/src/DsgPrs/DsgPrs_SymmetricPresentation.cxx
+++ b/src/DsgPrs/DsgPrs_SymmetricPresentation.cxx
@@ -75,13 +75,13 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
 
   gp_Pnt P1,P2;
 
-  //===================================
-  // SYMETRY OF EDGE PERPEND. TO THE AXIS    
+  //======================================
+  // SYMMETRY OF EDGE PERPEND. TO THE AXIS
   //   ____        :        ____
   // edge2 |       : -=-   | edge 1
   //       |<------:------>|
   //               :        
-  //===================================
+  //======================================
 
   if (VLa.Dot(VL1) == 0) {
     P1 = AttachmentPoint1.Translated(VLa);
@@ -124,7 +124,7 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
   
   /*=======================================================
    TO AVOID CROSSING
-          P1  -=- P2                P2  -=- P1         
+          P1  -=- P2                P2  -=- P1
             \<-->/                    |<-->|
              \  /                     |    |
               \/                      |    | 
@@ -143,13 +143,13 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
     PntTempo = P1;
     P1       = P2;
     P2       = PntTempo;
-  }  
+  }
   /*===================================
-   FRACTURES OF TRAITS OF CALL    
+   FRACTURES OF TRAITS OF CALL
           /             \		
          /               \	
          |      -=-      |
-         |<------------->| 
+         |<------------->|
   ===================================*/
 
   gp_Vec        Vfix;
@@ -226,7 +226,7 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
   }
 
   /*===================================
-   FRACTURES OF PROCESSING OF CALL    
+   FRACTURES OF PROCESSING OF CALL
                 -=-    
            |<--------->| 
            |           |   
@@ -395,8 +395,8 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
   aPrims->AddVertex(pOff.Translated(vec1.Reversed().Added(vec2.Reversed())));
 
   /*--------------------------------------------------------------------------------------
-  |                          MARKING OF THE SYMMETRY AXIS                             |
-  --------------------------------------------------------------------------------------     
+  |                          MARKING OF THE SYMMETRY AXIS                                |
+  ----------------------------------------------------------------------------------------
           ____
           \  / :Cursor
            \/
@@ -634,7 +634,7 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
   
 /*--------------------------------------------------------------------------------------
   |                          MARKING OF THE AXIS OF SYMMETRY                           |
-  --------------------------------------------------------------------------------------     
+  --------------------------------------------------------------------------------------
           ____
           \  / :Cursor
            \/
@@ -706,11 +706,11 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
     aPrims->AddVertex(OffsetPoint);
   
     //--------------------------------------------------------------------------------------
-    //|                                SYMBOL OF SYMMETRY                                 |
+    //|                                SYMBOL OF SYMMETRY                                  |
     //--------------------------------------------------------------------------------------
-    //           -------    : Superior Segment 
+    //           -------    : Superior Segment
     //         -----------  : Axis
-    //           -------    : Inferior Segment 
+    //           -------    : Inferior Segment
 
     //Calculate extremas of the axis of the symbol
     gp_Vec VAO (AttachmentPoint1,OffsetPoint);
@@ -824,7 +824,7 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
     //|                                SYMBOL OF SYMMETRY                                 |
     //-------------------------------------------------------------------------------------
     
-    //           -------    : Superior Segment 
+    //           -------    : Superior Segment
     //         -----------  : Axis
     //           -------    : Inferior Segment
     
@@ -866,8 +866,8 @@ void DsgPrs_SymmetricPresentation::Add (const Handle(Prs3d_Presentation)& aPrese
     aPrims->AddVertex(pOff.Translated(vec1.Reversed().Added(vec2.Reversed())));
 
     /*--------------------------------------------------------------------------------------
-    |                          MARKING OF THE AXIS OF SYMMETRY                           |
-    --------------------------------------------------------------------------------------     
+    |                          MARKING OF THE AXIS OF SYMMETRY                             |
+    ----------------------------------------------------------------------------------------
             ____
             \  / :Cursor
              \/
diff --git a/src/ElSLib/ElSLib.hxx b/src/ElSLib/ElSLib.hxx
index c4730f7180..a5a91f467f 100644
--- a/src/ElSLib/ElSLib.hxx
+++ b/src/ElSLib/ElSLib.hxx
@@ -153,7 +153,7 @@ public:
   //! Surface evaluation
   //! The following functions compute the point and the
   //! derivatives on elementary surfaces defined with their
-  //! geometric characterisitics.
+  //! geometric characteristics.
   //! You don't need to create the surface to use these functions.
   //! These functions are called by the previous  ones.
   //! Example :
diff --git a/src/Expr/Expr_BinaryExpression.hxx b/src/Expr/Expr_BinaryExpression.hxx
index b22d727482..504a7135e0 100644
--- a/src/Expr/Expr_BinaryExpression.hxx
+++ b/src/Expr/Expr_BinaryExpression.hxx
@@ -67,7 +67,7 @@ public:
   //! Tests if <me> contains <exp>.
   Standard_EXPORT Standard_Boolean Contains (const Handle(Expr_GeneralExpression)& exp) const Standard_OVERRIDE;
   
-  //! Replaces all occurences of <var> with <with> in <me>.
+  //! Replaces all occurrences of <var> with <with> in <me>.
   //! Raises InvalidOperand if <with> contains <me>.
   Standard_EXPORT void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) Standard_OVERRIDE;
   
diff --git a/src/Expr/Expr_GeneralExpression.hxx b/src/Expr/Expr_GeneralExpression.hxx
index 80f3d3c0ea..44895d9ef6 100644
--- a/src/Expr/Expr_GeneralExpression.hxx
+++ b/src/Expr/Expr_GeneralExpression.hxx
@@ -94,7 +94,7 @@ public:
   //! Raise OutOfRange if N <= 0
   Standard_EXPORT virtual Handle(Expr_GeneralExpression) NDerivative (const Handle(Expr_NamedUnknown)& X, const Standard_Integer N) const;
   
-  //! Replaces all occurences of <var> with copies of <with>
+  //! Replaces all occurrences of <var> with copies of <with>
   //! in <me>. Copies of <with> are made with the Copy() method.
   //! Raises InvalidOperand if <with> contains <me>.
   Standard_EXPORT virtual void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) = 0;
diff --git a/src/Expr/Expr_GeneralRelation.hxx b/src/Expr/Expr_GeneralRelation.hxx
index 28006980f8..d75b9d6277 100644
--- a/src/Expr/Expr_GeneralRelation.hxx
+++ b/src/Expr/Expr_GeneralRelation.hxx
@@ -74,7 +74,7 @@ public:
   //! Tests if <exp> contains <var>.
   Standard_EXPORT virtual Standard_Boolean Contains (const Handle(Expr_GeneralExpression)& exp) const = 0;
   
-  //! Replaces all occurences of <var> with <with> in <me>.
+  //! Replaces all occurrences of <var> with <with> in <me>.
   Standard_EXPORT virtual void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) = 0;
   
   //! returns a string representing <me> in a readable way.
diff --git a/src/Expr/Expr_NamedConstant.hxx b/src/Expr/Expr_NamedConstant.hxx
index 90be9b2921..53d44c92ba 100644
--- a/src/Expr/Expr_NamedConstant.hxx
+++ b/src/Expr/Expr_NamedConstant.hxx
@@ -84,7 +84,7 @@ public:
   //! Raises OutOfRange if <N> <= 0
   Standard_EXPORT virtual Handle(Expr_GeneralExpression) NDerivative (const Handle(Expr_NamedUnknown)& X, const Standard_Integer N) const Standard_OVERRIDE;
   
-  //! Replaces all occurences of <var> with <with> in <me>
+  //! Replaces all occurrences of <var> with <with> in <me>
   Standard_EXPORT void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) Standard_OVERRIDE;
   
   //! Returns the value of <me> (as a Real) by
diff --git a/src/Expr/Expr_NamedUnknown.hxx b/src/Expr/Expr_NamedUnknown.hxx
index 165104d771..78e656cd0a 100644
--- a/src/Expr/Expr_NamedUnknown.hxx
+++ b/src/Expr/Expr_NamedUnknown.hxx
@@ -60,7 +60,7 @@ public:
   //! Raises exception if <exp> refers to <me>.
   Standard_EXPORT void Assign (const Handle(Expr_GeneralExpression)& exp);
   
-  //! Supresses the assigned expression
+  //! Suppresses the assigned expression
     void Deassign();
   
   //! Returns the number of sub-expressions contained
@@ -94,7 +94,7 @@ public:
   //! Returns the derivative on <X> unknown of <me>
   Standard_EXPORT Handle(Expr_GeneralExpression) Derivative (const Handle(Expr_NamedUnknown)& X) const Standard_OVERRIDE;
   
-  //! Replaces all occurences of <var> with <with> in <me>
+  //! Replaces all occurrences of <var> with <with> in <me>
   //! Raises InvalidOperand if <with> contains <me>.
   Standard_EXPORT void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) Standard_OVERRIDE;
   
diff --git a/src/Expr/Expr_NumericValue.hxx b/src/Expr/Expr_NumericValue.hxx
index 7620c2399e..2d9b4dfbca 100644
--- a/src/Expr/Expr_NumericValue.hxx
+++ b/src/Expr/Expr_NumericValue.hxx
@@ -89,7 +89,7 @@ public:
   //! Raises OutOfRange if <N> <= 0
   Standard_EXPORT virtual Handle(Expr_GeneralExpression) NDerivative (const Handle(Expr_NamedUnknown)& X, const Standard_Integer N) const Standard_OVERRIDE;
   
-  //! Replaces all occurences of <var> with <with> in <me>
+  //! Replaces all occurrences of <var> with <with> in <me>
   Standard_EXPORT void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) Standard_OVERRIDE;
   
   //! Returns the value of <me> (as a Real) by
diff --git a/src/Expr/Expr_PolyExpression.hxx b/src/Expr/Expr_PolyExpression.hxx
index b3e3b495b9..cb70f40c1d 100644
--- a/src/Expr/Expr_PolyExpression.hxx
+++ b/src/Expr/Expr_PolyExpression.hxx
@@ -67,7 +67,7 @@ public:
   //! Tests if <exp> is contained in <me>.
   Standard_EXPORT Standard_Boolean Contains (const Handle(Expr_GeneralExpression)& exp) const Standard_OVERRIDE;
   
-  //! Replaces all occurences of <var> with <with> in <me>
+  //! Replaces all occurrences of <var> with <with> in <me>
   //! Raises InvalidOperand if <with> contains <me>.
   Standard_EXPORT void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) Standard_OVERRIDE;
   
diff --git a/src/Expr/Expr_Product.cxx b/src/Expr/Expr_Product.cxx
index 2aca663460..38f4acd02e 100644
--- a/src/Expr/Expr_Product.cxx
+++ b/src/Expr/Expr_Product.cxx
@@ -195,7 +195,7 @@ Handle(Expr_GeneralExpression) Expr_Product::ShallowSimplified () const
   for (i = 1; i <= max ; i++) {
     op = Operand(i);
     if (op->IsKind(STANDARD_TYPE(Expr_NumericValue))) {
-      // numeric operands are cumulated separetly
+      // numeric operands are cumulated separately
       Handle(Expr_NumericValue) NVop = Handle(Expr_NumericValue)::DownCast(op);
       if (nbvals == 0) {
 	noone = Standard_False;
diff --git a/src/Expr/Expr_SingleRelation.hxx b/src/Expr/Expr_SingleRelation.hxx
index d6455ce3c0..4a4147fd5f 100644
--- a/src/Expr/Expr_SingleRelation.hxx
+++ b/src/Expr/Expr_SingleRelation.hxx
@@ -68,7 +68,7 @@ public:
   //! Tests if <me> contains <exp>.
   Standard_EXPORT Standard_Boolean Contains (const Handle(Expr_GeneralExpression)& exp) const Standard_OVERRIDE;
   
-  //! Replaces all occurences of <var> with <with> in <me>.
+  //! Replaces all occurrences of <var> with <with> in <me>.
   Standard_EXPORT void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) Standard_OVERRIDE;
 
 
diff --git a/src/Expr/Expr_SystemRelation.hxx b/src/Expr/Expr_SystemRelation.hxx
index cf23653ef2..f8d5055308 100644
--- a/src/Expr/Expr_SystemRelation.hxx
+++ b/src/Expr/Expr_SystemRelation.hxx
@@ -83,7 +83,7 @@ public:
   //! Tests if <me> contains <exp>.
   Standard_EXPORT Standard_Boolean Contains (const Handle(Expr_GeneralExpression)& exp) const Standard_OVERRIDE;
   
-  //! Replaces all occurences of <var> with <with> in <me>.
+  //! Replaces all occurrences of <var> with <with> in <me>.
   Standard_EXPORT void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) Standard_OVERRIDE;
   
   //! returns a string representing <me> in a readable way.
diff --git a/src/Expr/Expr_UnaryExpression.hxx b/src/Expr/Expr_UnaryExpression.hxx
index ea98ff47b1..0fd9796712 100644
--- a/src/Expr/Expr_UnaryExpression.hxx
+++ b/src/Expr/Expr_UnaryExpression.hxx
@@ -61,7 +61,7 @@ public:
   //! Tests if <exp> is contained in <me>.
   Standard_EXPORT Standard_Boolean Contains (const Handle(Expr_GeneralExpression)& exp) const Standard_OVERRIDE;
   
-  //! Replaces all occurences of <var> with <with> in <me>
+  //! Replaces all occurrences of <var> with <with> in <me>
   //! Raises InvalidOperand if <with> contains <me>.
   Standard_EXPORT void Replace (const Handle(Expr_NamedUnknown)& var, const Handle(Expr_GeneralExpression)& with) Standard_OVERRIDE;
   
diff --git a/src/ExprIntrp/ExprIntrp_GenFct.hxx b/src/ExprIntrp/ExprIntrp_GenFct.hxx
index 31dc38c990..358fabd8ea 100644
--- a/src/ExprIntrp/ExprIntrp_GenFct.hxx
+++ b/src/ExprIntrp/ExprIntrp_GenFct.hxx
@@ -30,7 +30,7 @@ class ExprIntrp_GenFct;
 DEFINE_STANDARD_HANDLE(ExprIntrp_GenFct, ExprIntrp_Generator)
 
 //! Implements an interpreter for defining functions.
-//! All its functionnalities can be found in class
+//! All its functionalities can be found in class
 //! GenExp.
 class ExprIntrp_GenFct : public ExprIntrp_Generator
 {
diff --git a/src/Extrema/Extrema_ELPCOfLocateExtPC.hxx b/src/Extrema/Extrema_ELPCOfLocateExtPC.hxx
index cb8d6d41de..0e87959d20 100644
--- a/src/Extrema/Extrema_ELPCOfLocateExtPC.hxx
+++ b/src/Extrema/Extrema_ELPCOfLocateExtPC.hxx
@@ -57,7 +57,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! Zeros are searched between uinf and usup.
   //! Tol  is used to decide to stop the
@@ -68,7 +68,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! Tol is used to decide to stop the
   //! iterations according to the following condition:
diff --git a/src/Extrema/Extrema_ELPCOfLocateExtPC2d.hxx b/src/Extrema/Extrema_ELPCOfLocateExtPC2d.hxx
index 15191a7ff7..7dad307b7c 100644
--- a/src/Extrema/Extrema_ELPCOfLocateExtPC2d.hxx
+++ b/src/Extrema/Extrema_ELPCOfLocateExtPC2d.hxx
@@ -57,7 +57,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! Zeros are searched between uinf and usup.
   //! Tol  is used to decide to stop the
@@ -68,7 +68,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! Tol is used to decide to stop the
   //! iterations according to the following condition:
diff --git a/src/Extrema/Extrema_EPCOfELPCOfLocateExtPC.hxx b/src/Extrema/Extrema_EPCOfELPCOfLocateExtPC.hxx
index 4ffd1283ce..c1492ef44e 100644
--- a/src/Extrema/Extrema_EPCOfELPCOfLocateExtPC.hxx
+++ b/src/Extrema/Extrema_EPCOfELPCOfLocateExtPC.hxx
@@ -46,7 +46,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! NbU is used to locate the close points to
   //! find the zeros.
@@ -58,7 +58,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! NbU is used to locate the close points to
   //! find the zeros.
diff --git a/src/Extrema/Extrema_EPCOfELPCOfLocateExtPC2d.hxx b/src/Extrema/Extrema_EPCOfELPCOfLocateExtPC2d.hxx
index 040a7e9b1d..50d3e4b07c 100644
--- a/src/Extrema/Extrema_EPCOfELPCOfLocateExtPC2d.hxx
+++ b/src/Extrema/Extrema_EPCOfELPCOfLocateExtPC2d.hxx
@@ -46,7 +46,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! NbU is used to locate the close points to
   //! find the zeros.
@@ -58,7 +58,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! NbU is used to locate the close points to
   //! find the zeros.
diff --git a/src/Extrema/Extrema_EPCOfExtPC.hxx b/src/Extrema/Extrema_EPCOfExtPC.hxx
index b81e085d5e..2c0fe3c968 100644
--- a/src/Extrema/Extrema_EPCOfExtPC.hxx
+++ b/src/Extrema/Extrema_EPCOfExtPC.hxx
@@ -46,7 +46,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! NbU is used to locate the close points to
   //! find the zeros.
@@ -58,7 +58,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! NbU is used to locate the close points to
   //! find the zeros.
diff --git a/src/Extrema/Extrema_EPCOfExtPC2d.hxx b/src/Extrema/Extrema_EPCOfExtPC2d.hxx
index 33c8cc3eaa..0fd47f86ad 100644
--- a/src/Extrema/Extrema_EPCOfExtPC2d.hxx
+++ b/src/Extrema/Extrema_EPCOfExtPC2d.hxx
@@ -46,7 +46,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! NbU is used to locate the close points to
   //! find the zeros.
@@ -58,7 +58,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! NbU is used to locate the close points to
   //! find the zeros.
diff --git a/src/Extrema/Extrema_ExtElC.hxx b/src/Extrema/Extrema_ExtElC.hxx
index 28d1e28fef..8c35429a5b 100644
--- a/src/Extrema/Extrema_ExtElC.hxx
+++ b/src/Extrema/Extrema_ExtElC.hxx
@@ -56,7 +56,7 @@ public:
   Standard_EXPORT Extrema_ExtElC(const gp_Lin& C1, const gp_Circ& C2, const Standard_Real Tol);
   
   //! Calculates the distance between a line and an
-  //! elipse.
+  //! ellipse.
   Standard_EXPORT Extrema_ExtElC(const gp_Lin& C1, const gp_Elips& C2);
   
   //! Calculates the distance between a line and a
diff --git a/src/Extrema/Extrema_ExtElC2d.hxx b/src/Extrema/Extrema_ExtElC2d.hxx
index 891e0b6ed3..d7b064ac08 100644
--- a/src/Extrema/Extrema_ExtElC2d.hxx
+++ b/src/Extrema/Extrema_ExtElC2d.hxx
@@ -56,7 +56,7 @@ public:
   Standard_EXPORT Extrema_ExtElC2d(const gp_Lin2d& C1, const gp_Circ2d& C2, const Standard_Real Tol);
   
   //! Calculates the distance between a line and an
-  //! elipse.
+  //! ellipse.
   Standard_EXPORT Extrema_ExtElC2d(const gp_Lin2d& C1, const gp_Elips2d& C2);
   
   //! Calculates the distance between a line and a
@@ -72,7 +72,7 @@ public:
   Standard_EXPORT Extrema_ExtElC2d(const gp_Circ2d& C1, const gp_Circ2d& C2);
   
   //! Calculates the distance between a circle and an
-  //! elipse.
+  //! ellipse.
   Standard_EXPORT Extrema_ExtElC2d(const gp_Circ2d& C1, const gp_Elips2d& C2);
   
   //! Calculates the distance between a circle and a
diff --git a/src/Extrema/Extrema_ExtPC.hxx b/src/Extrema/Extrema_ExtPC.hxx
index fb6d4c550b..ef6fe40d27 100644
--- a/src/Extrema/Extrema_ExtPC.hxx
+++ b/src/Extrema/Extrema_ExtPC.hxx
@@ -57,7 +57,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! Zeros are searched between uinf and usup.
   //! Tol  is used to decide to stop the
@@ -68,7 +68,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! Tol is used to decide to stop the
   //! iterations according to the following condition:
diff --git a/src/Extrema/Extrema_ExtPC2d.hxx b/src/Extrema/Extrema_ExtPC2d.hxx
index 37c8e1e87c..ad0bb85dc5 100644
--- a/src/Extrema/Extrema_ExtPC2d.hxx
+++ b/src/Extrema/Extrema_ExtPC2d.hxx
@@ -57,7 +57,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! Zeros are searched between uinf and usup.
   //! Tol  is used to decide to stop the
@@ -68,7 +68,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs all the
+  //! when g(u)=dF/du=0. The algorithm searches all the
   //! zeros inside the definition range of the curve.
   //! Tol is used to decide to stop the
   //! iterations according to the following condition:
diff --git a/src/Extrema/Extrema_ExtPElC.hxx b/src/Extrema/Extrema_ExtPElC.hxx
index b8b1ad0597..19f2819160 100644
--- a/src/Extrema/Extrema_ExtPElC.hxx
+++ b/src/Extrema/Extrema_ExtPElC.hxx
@@ -70,12 +70,12 @@ public:
   Standard_EXPORT void Perform (const gp_Pnt& P, const gp_Circ& C, const Standard_Real Tol, const Standard_Real Uinf, const Standard_Real Usup);
   
   //! Calculates the 4 extremum distances between the
-  //! point P and the segment [Uinf,Usup] of the elipse C.
+  //! point P and the segment [Uinf,Usup] of the ellipse C.
   //! Tol is used to determine
-  //! if the point is on the axis of the elipse and
+  //! if the point is on the axis of the ellipse and
   //! if the major radius is equal to the minor radius or
   //! if an extremum is on an endpoint of the segment.
-  //! If P is on the axis of the elipse,
+  //! If P is on the axis of the ellipse,
   //! there are infinite solution then IsDone(me)=False.
   //! The conditions on the Uinf and Usup are:
   //! 0. <= Uinf <= 2.*PI and Usup > Uinf.
diff --git a/src/Extrema/Extrema_ExtPElC2d.hxx b/src/Extrema/Extrema_ExtPElC2d.hxx
index 66d0e002bd..79cdc01a6b 100644
--- a/src/Extrema/Extrema_ExtPElC2d.hxx
+++ b/src/Extrema/Extrema_ExtPElC2d.hxx
@@ -70,12 +70,12 @@ public:
   Standard_EXPORT void Perform (const gp_Pnt2d& P, const gp_Circ2d& C, const Standard_Real Tol, const Standard_Real Uinf, const Standard_Real Usup);
   
   //! Calculates the 4 extremum distances between the
-  //! point P and the segment [Uinf,Usup] of the elipse C.
+  //! point P and the segment [Uinf,Usup] of the ellipse C.
   //! Tol is used to determine
-  //! if the point is on the axis of the elipse and
+  //! if the point is on the axis of the ellipse and
   //! if the major radius is equal to the minor radius or
   //! if an extremum is on an endpoint of the segment.
-  //! If P is on the axis of the elipse,
+  //! If P is on the axis of the ellipse,
   //! there are infinite solution then IsDone(me)=False.
   //! The conditions on the Uinf and Usup are:
   //! 0. <= Uinf <= 2.*PI and Usup > Uinf.
diff --git a/src/Extrema/Extrema_ExtPRevS.cxx b/src/Extrema/Extrema_ExtPRevS.cxx
index 4f9c1f212b..93e3347ca9 100644
--- a/src/Extrema/Extrema_ExtPRevS.cxx
+++ b/src/Extrema/Extrema_ExtPRevS.cxx
@@ -51,7 +51,7 @@ static gp_Ax2 GetPosition (const GeomAdaptor_SurfaceOfRevolution& S)//const Hand
       if (OO.Magnitude() <= gp::Resolution()) {
 	OO = gp_Vec(L.Location(), ElCLib::Value(100,L));
 	if (N.IsParallel(OO, Precision::Angular()))
-	  return gp_Ax2(); // Line and axe of revolution coinside
+	  return gp_Ax2(); // Line and axe of revolution coincide
       }
       N ^= OO;
     }
diff --git a/src/Extrema/Extrema_GExtPC.gxx b/src/Extrema/Extrema_GExtPC.gxx
index e9f76104a6..a06710a5d1 100644
--- a/src/Extrema/Extrema_GExtPC.gxx
+++ b/src/Extrema/Extrema_GExtPC.gxx
@@ -156,7 +156,7 @@ void Extrema_GExtPC::Perform(const ThePoint& P)
 
       if (mysample == 2)
       {
-        //BSpline of first degree, direct seaching extrema for each knot interval
+        //BSpline of first degree, direct searching extrema for each knot interval
         ThePoint aPmin;
         Standard_Real tmin = 0., distmin = RealLast();
         Standard_Real aMin1 = 0., aMin2 = 0.;
diff --git a/src/Extrema/Extrema_GenExtCS.hxx b/src/Extrema/Extrema_GenExtCS.hxx
index 932a746cb2..2f043a8ef6 100644
--- a/src/Extrema/Extrema_GenExtCS.hxx
+++ b/src/Extrema/Extrema_GenExtCS.hxx
@@ -52,7 +52,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u,v)=distance(S1(u1,v1),S2(u2,v2)) has an
-  //! extremum when gradient(F)=0. The algorithm searchs
+  //! extremum when gradient(F)=0. The algorithm searches
   //! all the zeros inside the definition ranges of the
   //! surfaces.
   //! NbU and NbV are used to locate the close points on the
@@ -61,7 +61,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u,v)=distance(P,S(u,v)) has an
-  //! extremum when gradient(F)=0. The algorithm searchs
+  //! extremum when gradient(F)=0. The algorithm searches
   //! all the zeros inside the definition ranges of the
   //! surface.
   //! NbT,NbU and NbV are used to locate the close points
diff --git a/src/Extrema/Extrema_GenExtPS.hxx b/src/Extrema/Extrema_GenExtPS.hxx
index 3ad87ef279..389469ca13 100644
--- a/src/Extrema/Extrema_GenExtPS.hxx
+++ b/src/Extrema/Extrema_GenExtPS.hxx
@@ -56,7 +56,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u,v)=distance(P,S(u,v)) has an
-  //! extremum when gradient(F)=0. The algorithm searchs
+  //! extremum when gradient(F)=0. The algorithm searches
   //! all the zeros inside the definition ranges of the
   //! surface.
   //! NbU and NbV are used to locate the close points
@@ -70,7 +70,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u,v)=distance(P,S(u,v)) has an
-  //! extremum when gradient(F)=0. The algorithm searchs
+  //! extremum when gradient(F)=0. The algorithm searches
   //! all the zeros inside the definition ranges of the
   //! surface.
   //! NbU and NbV are used to locate the close points
diff --git a/src/Extrema/Extrema_GenExtSS.hxx b/src/Extrema/Extrema_GenExtSS.hxx
index 6699e2d4dd..cc36cf50c7 100644
--- a/src/Extrema/Extrema_GenExtSS.hxx
+++ b/src/Extrema/Extrema_GenExtSS.hxx
@@ -48,7 +48,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u,v)=distance(S1(u1,v1),S2(u2,v2)) has an
-  //! extremum when gradient(F)=0. The algorithm searchs
+  //! extremum when gradient(F)=0. The algorithm searches
   //! all the zeros inside the definition ranges of the
   //! surfaces.
   //! NbU and NbV are used to locate the close points
@@ -57,7 +57,7 @@ public:
   
   //! It calculates all the distances.
   //! The function F(u,v)=distance(P,S(u,v)) has an
-  //! extremum when gradient(F)=0. The algorithm searchs
+  //! extremum when gradient(F)=0. The algorithm searches
   //! all the zeros inside the definition ranges of the
   //! surface.
   //! NbU and NbV are used to locate the close points
diff --git a/src/Extrema/Extrema_GenLocateExtCS.hxx b/src/Extrema/Extrema_GenLocateExtCS.hxx
index da3b395803..9f15955601 100644
--- a/src/Extrema/Extrema_GenLocateExtCS.hxx
+++ b/src/Extrema/Extrema_GenLocateExtCS.hxx
@@ -49,7 +49,7 @@ public:
   //! The close points are defined by the parameter values
   //! T for C and (U,V) for S.
   //! The function F(t,u,v)=distance(C(t),S(u,v))
-  //! has an extremun when gradient(F)=0. The algorithm searchs
+  //! has an extremun when gradient(F)=0. The algorithm searches
   //! a zero near the close points.
   Standard_EXPORT Extrema_GenLocateExtCS(const Adaptor3d_Curve& C, const Adaptor3d_Surface& S, const Standard_Real T, const Standard_Real U, const Standard_Real V, const Standard_Real Tol1, const Standard_Real Tol2);
   
diff --git a/src/Extrema/Extrema_GenLocateExtSS.hxx b/src/Extrema/Extrema_GenLocateExtSS.hxx
index a51dd44aaf..da45d81869 100644
--- a/src/Extrema/Extrema_GenLocateExtSS.hxx
+++ b/src/Extrema/Extrema_GenLocateExtSS.hxx
@@ -46,7 +46,7 @@ public:
   //! The close points are defined by the parameter values
   //! (U1,V1) for S1 and (U2,V2) for S2.
   //! The function F(u1,v1,u2,v2)=distance(S1(u1,v1),S2(u2,v2))
-  //! has an extremun when gradient(F)=0. The algorithm searchs
+  //! has an extremun when gradient(F)=0. The algorithm searches
   //! a zero near the close points.
   Standard_EXPORT Extrema_GenLocateExtSS(const Adaptor3d_Surface& S1, const Adaptor3d_Surface& S2, const Standard_Real U1, const Standard_Real V1, const Standard_Real U2, const Standard_Real V2, const Standard_Real Tol1, const Standard_Real Tol2);
   
diff --git a/src/Extrema/Extrema_LocECC.hxx b/src/Extrema/Extrema_LocECC.hxx
index a4d5b0c83b..ba9bbbfb86 100644
--- a/src/Extrema/Extrema_LocECC.hxx
+++ b/src/Extrema/Extrema_LocECC.hxx
@@ -46,7 +46,7 @@ public:
   //! close point is defined by a parameter value on each
   //! curve.
   //! The function F(u,v)=distance(C1(u),C2(v)) has an
-  //! extremun when gradient(f)=0. The algorithm searchs
+  //! extremun when gradient(f)=0. The algorithm searches
   //! the zero near the close point.
   Standard_EXPORT Extrema_LocECC(const Adaptor3d_Curve& C1, const Adaptor3d_Curve& C2, const Standard_Real U0, const Standard_Real V0, const Standard_Real TolU, const Standard_Real TolV);
   
diff --git a/src/Extrema/Extrema_LocECC2d.hxx b/src/Extrema/Extrema_LocECC2d.hxx
index 68efddb71c..1c05252e7b 100644
--- a/src/Extrema/Extrema_LocECC2d.hxx
+++ b/src/Extrema/Extrema_LocECC2d.hxx
@@ -46,7 +46,7 @@ public:
   //! close point is defined by a parameter value on each
   //! curve.
   //! The function F(u,v)=distance(C1(u),C2(v)) has an
-  //! extremun when gradient(f)=0. The algorithm searchs
+  //! extremun when gradient(f)=0. The algorithm searches
   //! the zero near the close point.
   Standard_EXPORT Extrema_LocECC2d(const Adaptor2d_Curve2d& C1, const Adaptor2d_Curve2d& C2, const Standard_Real U0, const Standard_Real V0, const Standard_Real TolU, const Standard_Real TolV);
   
diff --git a/src/Extrema/Extrema_LocEPCOfLocateExtPC.hxx b/src/Extrema/Extrema_LocEPCOfLocateExtPC.hxx
index c17faf65ec..2565f2e683 100644
--- a/src/Extrema/Extrema_LocEPCOfLocateExtPC.hxx
+++ b/src/Extrema/Extrema_LocEPCOfLocateExtPC.hxx
@@ -47,7 +47,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! TolU is used to decide to stop the iterations.
   //! At the nth iteration, the criteria is:
@@ -58,7 +58,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! Zeros are searched between Umin et Usup.
   //! TolU is used to decide to stop the iterations.
diff --git a/src/Extrema/Extrema_LocEPCOfLocateExtPC2d.hxx b/src/Extrema/Extrema_LocEPCOfLocateExtPC2d.hxx
index f6c667f3cc..aafc6afa44 100644
--- a/src/Extrema/Extrema_LocEPCOfLocateExtPC2d.hxx
+++ b/src/Extrema/Extrema_LocEPCOfLocateExtPC2d.hxx
@@ -47,7 +47,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! TolU is used to decide to stop the iterations.
   //! At the nth iteration, the criteria is:
@@ -58,7 +58,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! Zeros are searched between Umin et Usup.
   //! TolU is used to decide to stop the iterations.
diff --git a/src/Extrema/Extrema_LocateExtCC.hxx b/src/Extrema/Extrema_LocateExtCC.hxx
index 58e806a54d..8dc46b260a 100644
--- a/src/Extrema/Extrema_LocateExtCC.hxx
+++ b/src/Extrema/Extrema_LocateExtCC.hxx
@@ -44,7 +44,7 @@ public:
   //! close point is defined by a parameter value on each
   //! curve.
   //! The function F(u,v)=distance(C1(u),C2(v)) has an
-  //! extremun when gradient(f)=0. The algorithm searchs
+  //! extremun when gradient(f)=0. The algorithm searches
   //! the zero near the close point.
   Standard_EXPORT Extrema_LocateExtCC(const Adaptor3d_Curve& C1, const Adaptor3d_Curve& C2, const Standard_Real U0, const Standard_Real V0);
   
diff --git a/src/Extrema/Extrema_LocateExtCC2d.hxx b/src/Extrema/Extrema_LocateExtCC2d.hxx
index f8f7b8af67..13df143e07 100644
--- a/src/Extrema/Extrema_LocateExtCC2d.hxx
+++ b/src/Extrema/Extrema_LocateExtCC2d.hxx
@@ -44,7 +44,7 @@ public:
   //! close point is defined by a parameter value on each
   //! curve.
   //! The function F(u,v)=distance(C1(u),C2(v)) has an
-  //! extremun when gradient(f)=0. The algorithm searchs
+  //! extremun when gradient(f)=0. The algorithm searches
   //! the zero near the close point.
   Standard_EXPORT Extrema_LocateExtCC2d(const Adaptor2d_Curve2d& C1, const Adaptor2d_Curve2d& C2, const Standard_Real U0, const Standard_Real V0);
   
diff --git a/src/Extrema/Extrema_LocateExtPC.hxx b/src/Extrema/Extrema_LocateExtPC.hxx
index 673bf1d870..b646920974 100644
--- a/src/Extrema/Extrema_LocateExtPC.hxx
+++ b/src/Extrema/Extrema_LocateExtPC.hxx
@@ -58,7 +58,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! TolF is used to decide to stop the iterations.
   //! At the nth iteration, the criteria is:
@@ -69,7 +69,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! Zeros are searched between Umin et Usup.
   //! TolF is used to decide to stop the iterations.
diff --git a/src/Extrema/Extrema_LocateExtPC2d.hxx b/src/Extrema/Extrema_LocateExtPC2d.hxx
index 73e6cd1cbb..28274c1755 100644
--- a/src/Extrema/Extrema_LocateExtPC2d.hxx
+++ b/src/Extrema/Extrema_LocateExtPC2d.hxx
@@ -58,7 +58,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! TolF is used to decide to stop the iterations.
   //! At the nth iteration, the criteria is:
@@ -69,7 +69,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! Zeros are searched between Umin et Usup.
   //! TolF is used to decide to stop the iterations.
diff --git a/src/Extrema/Extrema_PCFOfEPCOfELPCOfLocateExtPC.hxx b/src/Extrema/Extrema_PCFOfEPCOfELPCOfLocateExtPC.hxx
index a803503354..36d79c45f6 100644
--- a/src/Extrema/Extrema_PCFOfEPCOfELPCOfLocateExtPC.hxx
+++ b/src/Extrema/Extrema_PCFOfEPCOfELPCOfLocateExtPC.hxx
@@ -67,7 +67,7 @@ public:
   //! Save the found extremum.
   Standard_EXPORT virtual Standard_Integer GetStateNumber() Standard_OVERRIDE;
   
-  //! Return the nunber of found extrema.
+  //! Return the number of found extrema.
   Standard_EXPORT Standard_Integer NbExt() const;
   
   //! Returns the Nth distance.
diff --git a/src/Extrema/Extrema_PCFOfEPCOfELPCOfLocateExtPC2d.hxx b/src/Extrema/Extrema_PCFOfEPCOfELPCOfLocateExtPC2d.hxx
index 9708eba001..b2e49b9fea 100644
--- a/src/Extrema/Extrema_PCFOfEPCOfELPCOfLocateExtPC2d.hxx
+++ b/src/Extrema/Extrema_PCFOfEPCOfELPCOfLocateExtPC2d.hxx
@@ -67,7 +67,7 @@ public:
   //! Save the found extremum.
   Standard_EXPORT virtual Standard_Integer GetStateNumber() Standard_OVERRIDE;
   
-  //! Return the nunber of found extrema.
+  //! Return the number of found extrema.
   Standard_EXPORT Standard_Integer NbExt() const;
   
   //! Returns the Nth distance.
diff --git a/src/Extrema/Extrema_PCFOfEPCOfExtPC.hxx b/src/Extrema/Extrema_PCFOfEPCOfExtPC.hxx
index 7199fc2d32..287128dee4 100644
--- a/src/Extrema/Extrema_PCFOfEPCOfExtPC.hxx
+++ b/src/Extrema/Extrema_PCFOfEPCOfExtPC.hxx
@@ -67,7 +67,7 @@ public:
   //! Save the found extremum.
   Standard_EXPORT virtual Standard_Integer GetStateNumber() Standard_OVERRIDE;
   
-  //! Return the nunber of found extrema.
+  //! Return the number of found extrema.
   Standard_EXPORT Standard_Integer NbExt() const;
   
   //! Returns the Nth distance.
diff --git a/src/Extrema/Extrema_PCFOfEPCOfExtPC2d.hxx b/src/Extrema/Extrema_PCFOfEPCOfExtPC2d.hxx
index cfa3da7f79..d8936cb89a 100644
--- a/src/Extrema/Extrema_PCFOfEPCOfExtPC2d.hxx
+++ b/src/Extrema/Extrema_PCFOfEPCOfExtPC2d.hxx
@@ -67,7 +67,7 @@ public:
   //! Save the found extremum.
   Standard_EXPORT virtual Standard_Integer GetStateNumber() Standard_OVERRIDE;
   
-  //! Return the nunber of found extrema.
+  //! Return the number of found extrema.
   Standard_EXPORT Standard_Integer NbExt() const;
   
   //! Returns the Nth distance.
diff --git a/src/Extrema/Extrema_PCLocFOfLocEPCOfLocateExtPC.hxx b/src/Extrema/Extrema_PCLocFOfLocEPCOfLocateExtPC.hxx
index 492d6bc358..b19d3a8fed 100644
--- a/src/Extrema/Extrema_PCLocFOfLocEPCOfLocateExtPC.hxx
+++ b/src/Extrema/Extrema_PCLocFOfLocEPCOfLocateExtPC.hxx
@@ -67,7 +67,7 @@ public:
   //! Save the found extremum.
   Standard_EXPORT virtual Standard_Integer GetStateNumber() Standard_OVERRIDE;
   
-  //! Return the nunber of found extrema.
+  //! Return the number of found extrema.
   Standard_EXPORT Standard_Integer NbExt() const;
   
   //! Returns the Nth distance.
diff --git a/src/Extrema/Extrema_PCLocFOfLocEPCOfLocateExtPC2d.hxx b/src/Extrema/Extrema_PCLocFOfLocEPCOfLocateExtPC2d.hxx
index ecef1b2527..e264dc23a2 100644
--- a/src/Extrema/Extrema_PCLocFOfLocEPCOfLocateExtPC2d.hxx
+++ b/src/Extrema/Extrema_PCLocFOfLocEPCOfLocateExtPC2d.hxx
@@ -67,7 +67,7 @@ public:
   //! Save the found extremum.
   Standard_EXPORT virtual Standard_Integer GetStateNumber() Standard_OVERRIDE;
   
-  //! Return the nunber of found extrema.
+  //! Return the number of found extrema.
   Standard_EXPORT Standard_Integer NbExt() const;
   
   //! Returns the Nth distance.
diff --git a/src/FairCurve/FairCurve_Batten.cxx b/src/FairCurve/FairCurve_Batten.cxx
index ea843f9e28..4a438529d4 100644
--- a/src/FairCurve/FairCurve_Batten.cxx
+++ b/src/FairCurve/FairCurve_Batten.cxx
@@ -309,7 +309,7 @@ Standard_Boolean FairCurve_Batten::Compute(const gp_Vec2d& DeltaP1,
  Angle1 =  Ox.Angle(P1P2) + Alph1;
  Angle2 = -Ox.Angle(P1P2) + Alph2;
 
-// Calculation of the length of sliding (imposed or intial);
+// Calculation of the length of sliding (imposed or initial);
  
  if (!NewFreeSliding) {
     SlidingLength = NewSlidingFactor * LReference;
diff --git a/src/FilletSurf/FilletSurf_Builder.cxx b/src/FilletSurf/FilletSurf_Builder.cxx
index df9475f6f7..e1a9359bcc 100644
--- a/src/FilletSurf/FilletSurf_Builder.cxx
+++ b/src/FilletSurf/FilletSurf_Builder.cxx
@@ -242,7 +242,7 @@ Standard_Real FilletSurf_Builder::LastParameter() const
 //                                on the edge of  the corresponding support face.  
 //            OneExtremityOnEdge: only one  of  the extremities of  start section  of the  Fillet 
 //                                is on the  edge of the corresponding support face.  
-//            NoExtremityOnEdge:  any extremity of  the start section  ofthe fillet is  on  
+//            NoExtremityOnEdge:  any extremity of  the start section  of the fillet is  on  
 //                                the edge  of   the  corresponding support face.
 //=======================================================================
 FilletSurf_StatusType  FilletSurf_Builder::StartSectionStatus() const 
diff --git a/src/Font/Font_FontMgr.cxx b/src/Font/Font_FontMgr.cxx
index fabb06dffa..620f841018 100644
--- a/src/Font/Font_FontMgr.cxx
+++ b/src/Font/Font_FontMgr.cxx
@@ -778,7 +778,7 @@ void Font_FontMgr::InitFontDataBase()
           Standard_Integer aPathNumber = 1;
           do
           {
-            // Getting directory paths, which can be splitted by "," or ":"
+            // Getting directory paths, which can be split by "," or ":"
             aFontPath = aStr.Token (":,", aPathNumber);
             aFontPath.RightAdjust();
             if (!aFontPath.IsEmpty())
@@ -877,7 +877,7 @@ void Font_FontMgr::InitFontDataBase()
       if (aSupportedExtensions.Contains (aFontExtension) && (aLine.Search (anEncoding) > 0))
       {
         // In current implementation use fonts with ISO-8859-1 coding page.
-        // OCCT not give to manage coding page by means of programm interface.
+        // OCCT not give to manage coding page by means of program interface.
         // TODO: make high level interface for choosing necessary coding page.
         TCollection_AsciiString aXLFD (aLine.SubString (anEndOfFileName + 2, aLine.Length()));
         TCollection_AsciiString aFontPath (anIter.Value().ToCString());
diff --git a/src/GC/GC_MakeMirror.hxx b/src/GC/GC_MakeMirror.hxx
index 78fcc46b28..9de369241c 100644
--- a/src/GC/GC_MakeMirror.hxx
+++ b/src/GC/GC_MakeMirror.hxx
@@ -50,14 +50,14 @@ public:
   
   Standard_EXPORT GC_MakeMirror(const gp_Lin& Line);
   
-  //! Make a symetry transformation af axis defined by
+  //! Make a symmetry transformation af axis defined by
   //! <Point> and <Direc>.
   Standard_EXPORT GC_MakeMirror(const gp_Pnt& Point, const gp_Dir& Direc);
   
-  //! Make a symetry transformation of plane <Plane>.
+  //! Make a symmetry transformation of plane <Plane>.
   Standard_EXPORT GC_MakeMirror(const gp_Pln& Plane);
   
-  //! Make a symetry transformation of plane <Plane>.
+  //! Make a symmetry transformation of plane <Plane>.
   Standard_EXPORT GC_MakeMirror(const gp_Ax2& Plane);
   
   //! Returns the constructed transformation.
diff --git a/src/GC/GC_MakePlane.hxx b/src/GC/GC_MakePlane.hxx
index f7e994d643..0cdfb035b1 100644
--- a/src/GC/GC_MakePlane.hxx
+++ b/src/GC/GC_MakePlane.hxx
@@ -74,7 +74,7 @@ public:
   //! In the first case the result is at the distance
   //! <Dist> to the plane <Pln> in the direction of the
   //! normal to <Pln>.
-  //! Otherwise it is in the oposite direction.
+  //! Otherwise it is in the opposite direction.
   Standard_EXPORT GC_MakePlane(const gp_Pln& Pln, const Standard_Real Dist);
   
   //! Make a Plane from Geom <ThePlane> passing through 3
diff --git a/src/GC/GC_MakeTrimmedCylinder.hxx b/src/GC/GC_MakeTrimmedCylinder.hxx
index 308de0505e..18ffbd470d 100644
--- a/src/GC/GC_MakeTrimmedCylinder.hxx
+++ b/src/GC/GC_MakeTrimmedCylinder.hxx
@@ -47,7 +47,7 @@ public:
 
   
   //! Make a cylindricalSurface <Cyl> from Geom
-  //! Its axis is is <P1P2> and its radius is the distance
+  //! Its axis is <P1P2> and its radius is the distance
   //! between <P3> and <P1P2>.
   //! The height is the distance between P1 and P2.
   Standard_EXPORT GC_MakeTrimmedCylinder(const gp_Pnt& P1, const gp_Pnt& P2, const gp_Pnt& P3);
diff --git a/src/GCE2d/GCE2d_MakeMirror.hxx b/src/GCE2d/GCE2d_MakeMirror.hxx
index 1b8daa94fc..289acf3584 100644
--- a/src/GCE2d/GCE2d_MakeMirror.hxx
+++ b/src/GCE2d/GCE2d_MakeMirror.hxx
@@ -48,7 +48,7 @@ public:
   
   Standard_EXPORT GCE2d_MakeMirror(const gp_Lin2d& Line);
   
-  //! Make a symetry transformation af axis defined by
+  //! Make a symmetry transformation af axis defined by
   //! <Point> and <Direc>.
   Standard_EXPORT GCE2d_MakeMirror(const gp_Pnt2d& Point, const gp_Dir2d& Direc);
   
diff --git a/src/GCPnts/GCPnts_AbscissaPoint.pxx b/src/GCPnts/GCPnts_AbscissaPoint.pxx
index dfed3b6e7e..480e9559fb 100644
--- a/src/GCPnts/GCPnts_AbscissaPoint.pxx
+++ b/src/GCPnts/GCPnts_AbscissaPoint.pxx
@@ -14,7 +14,7 @@
 // Alternatively, this file may be used under the terms of Open CASCADE
 // commercial license or contractual agreement.
 
-// Dimension independant used to implement GCPnts_AbscissaPoint
+// Dimension independent used to implement GCPnts_AbscissaPoint
 
 // compute the type 
 // and the length ratio if GCPnts_LengthParametrized
@@ -158,7 +158,7 @@ static void Compute(CPnts_AbscissaPoint& theComputer,
 }
 
 // introduced by rbv for curvilinear parametrization
-// performs more appropriate tolerance managment
+// performs more appropriate tolerance management
 
 static void AdvCompute(CPnts_AbscissaPoint& theComputer,
                     const TheCurve& C,
diff --git a/src/GCPnts/GCPnts_TangentialDeflection.pxx b/src/GCPnts/GCPnts_TangentialDeflection.pxx
index deadfb6309..5cc7038773 100644
--- a/src/GCPnts/GCPnts_TangentialDeflection.pxx
+++ b/src/GCPnts/GCPnts_TangentialDeflection.pxx
@@ -619,7 +619,7 @@ void GCPnts_TangentialDeflection::PerformCurve (const TheCurve& C)
           parameters.InsertAfter(i, umax);
           points.InsertAfter(i, MiddlePoint);
           ++Nbp;
-          --i; //To compensate ++i in loop header: i must point to first part of splitted interval
+          --i; //To compensate ++i in loop header: i must point to first part of split interval
           if(Nbp > MaxNbp)
           {
             break;
diff --git a/src/GCPnts/GCPnts_UniformAbscissa.pxx b/src/GCPnts/GCPnts_UniformAbscissa.pxx
index 7247fc6699..6a505f7ebc 100644
--- a/src/GCPnts/GCPnts_UniformAbscissa.pxx
+++ b/src/GCPnts/GCPnts_UniformAbscissa.pxx
@@ -313,7 +313,7 @@ void GCPnts_UniformAbscissa::Initialize(const TheCurve& C,
 // 
 //  compute the total Length here so that we can 
 //  guess the number of points instead of letting the
-//  constructor of CPnts_AbscissaPoint do that and loosing
+//  constructor of CPnts_AbscissaPoint do that and lose
 //  the information
 //
 //
@@ -422,7 +422,7 @@ void GCPnts_UniformAbscissa::Initialize(const TheCurve& C,
 // 
 //  compute the total Length here so that we can 
 //  guess the number of points instead of letting the
-//  constructor of CPnts_AbscissaPoint do that and loosing
+//  constructor of CPnts_AbscissaPoint do that and lose
 //  the information
 //
 //
diff --git a/src/GProp/GProp.hxx b/src/GProp/GProp.hxx
index 8ed6655b5d..794232d54b 100644
--- a/src/GProp/GProp.hxx
+++ b/src/GProp/GProp.hxx
@@ -34,7 +34,7 @@ class GProp_PEquation;
 
 
 
-//! This package defines algorithmes to compute the global properties
+//! This package defines algorithms to compute the global properties
 //! of a set of points, a curve, a surface, a solid (non infinite
 //! region of space delimited with geometric entities), a compound
 //! geometric system (heterogeneous composition of the previous
diff --git a/src/GProp/GProp_PrincipalProps.hxx b/src/GProp/GProp_PrincipalProps.hxx
index a14c7715e8..fecae24883 100644
--- a/src/GProp/GProp_PrincipalProps.hxx
+++ b/src/GProp/GProp_PrincipalProps.hxx
@@ -69,7 +69,7 @@ public:
   
 
   //! returns true if the geometric system has an axis of symmetry.
-  //! aTol  is  relative  tolerance for  cheking  equality  of  moments
+  //! aTol  is  relative  tolerance for  checking  equality  of  moments
   //! If  aTol  ==  0,  relative  tolerance  is  ~  1.e-16  (Epsilon(I))
   Standard_EXPORT Standard_Boolean HasSymmetryAxis (const Standard_Real aTol) const;
   
@@ -82,7 +82,7 @@ public:
   
 
   //! returns true if the geometric system has a point of symmetry.
-  //! aTol  is  relative  tolerance for  cheking  equality  of  moments
+  //! aTol  is  relative  tolerance for  checking  equality  of  moments
   //! If  aTol  ==  0,  relative  tolerance  is  ~  1.e-16  (Epsilon(I))
   Standard_EXPORT Standard_Boolean HasSymmetryPoint (const Standard_Real aTol) const;
   
diff --git a/src/GccAna/GccAna_Circ2d3Tan.cxx b/src/GccAna/GccAna_Circ2d3Tan.cxx
index 53382a3b46..a194cadc63 100644
--- a/src/GccAna/GccAna_Circ2d3Tan.cxx
+++ b/src/GccAna/GccAna_Circ2d3Tan.cxx
@@ -184,10 +184,11 @@ GccAna_Circ2d3Tan::
 //   7)  <  (X - X2)2 + (Y - Y2)2 = (R + R2)2   8)  <  (X - X2)2 + (Y - Y2)2 = (R + R2)2
 //        \_(X - X3)2 + (Y - Y3)2 = (R + R3)2        \_(X - X3)2 + (Y - Y3)2 = (R + R3)2
 
-//   each equation (X - Xi)2 + (Y - Yi)2 = (R +- Ri)2 means that the circle (X,Y,R) is tangent 
+//   each equation (X - Xi)2 + (Y - Yi)2 = (R +- Ri)2 means that the circle (X,Y,R) is tangent
 //   to the circle (Xi,Yi,Ri).
 
-//   The number of each system is very important. Further index i shows the numer of the system
+//   The number of each system is very important.
+//   Further index i shows the number of the system.
 
 //   Further Beta, Gamma and Delta are coefficients of the equation:
 //                R +- Ri = Beta*X + Gamma*Y + Delta  where i=2 or i=3
diff --git a/src/GccAna/GccAna_Circ2d3Tan.hxx b/src/GccAna/GccAna_Circ2d3Tan.hxx
index 0fc9ee7476..873d715507 100644
--- a/src/GccAna/GccAna_Circ2d3Tan.hxx
+++ b/src/GccAna/GccAna_Circ2d3Tan.hxx
@@ -54,7 +54,7 @@ class gp_Circ2d;
 //! If we do not use Tolerance it is impossible to find
 //! a solution in the following case : C2 is inside C1
 //! and there is no intersection point between the two
-//! circles, and C3 is completly outside C1.
+//! circles, and C3 is completely outside C1.
 //! With Tolerance we will find a solution if the
 //! lowest distance between C1 and C2 is lower than or
 //! equal Tolerance.
@@ -110,20 +110,20 @@ public:
   
   //! This method implements the algorithms used to
   //! create 2d circles tangent to a circle and passing
-  //! thrue 2 Points.
+  //! through 2 Points.
   //! ConstructionError is raised if there is a problem during
   //! the computation.
   Standard_EXPORT GccAna_Circ2d3Tan(const GccEnt_QualifiedCirc& Qualified1, const gp_Pnt2d& Point2, const gp_Pnt2d& Point3, const Standard_Real Tolerance);
   
   //! This method implements the algorithms used to
   //! create 2d circles tangent to a line and passing
-  //! thrue 2 Points.
+  //! through 2 Points.
   //! ConstructionError is raised if there is a problem during
   //! the computation.
   Standard_EXPORT GccAna_Circ2d3Tan(const GccEnt_QualifiedLin& Qualified1, const gp_Pnt2d& Point2, const gp_Pnt2d& Point3, const Standard_Real Tolerance);
   
   //! This method implements the algorithms used to
-  //! create 2d circles passing thrue 3 Points.
+  //! create 2d circles passing through 3 Points.
   //! ConstructionError is raised if there is a problem during
   //! the computation.
   Standard_EXPORT GccAna_Circ2d3Tan(const gp_Pnt2d& Point1, const gp_Pnt2d& Point2, const gp_Pnt2d& Point3, const Standard_Real Tolerance);
diff --git a/src/GccAna/GccAna_Circ2dBisec.cxx b/src/GccAna/GccAna_Circ2dBisec.cxx
index c07893c36c..d687166e75 100644
--- a/src/GccAna/GccAna_Circ2dBisec.cxx
+++ b/src/GccAna/GccAna_Circ2dBisec.cxx
@@ -45,14 +45,14 @@ GccAna_Circ2dBisec::
 
 //=========================================================================
 //  Initialization of fields :                                            +
-//            - circle1  (Circle : first argument.)                       +
-//            - circle2  (Line   : second argument.)                      +
-//            - intersection (Integer showing the smallest position       +
-//                            of two circles correspondingly to each other.) +
-//            - sameradius   (Booleen showing if the two circles have   +
-//                            the same radius or not.)                         +
-//            - NbrSol   (Integer showing the number of solutions.)       +
-//            - WellDone (Boolean showing succes or failure of the algo.). +
+//            - circle1  (Circle : first argument)                        +
+//            - circle2  (Line   : second argument)                       +
+//            - intersection (Integer showing the smallest position of    +
+//                            two circles correspondingly to each other)  +
+//            - sameradius   (Boolean showing if the two circles have     +
+//                            the same radius or not)                     +
+//            - NbrSol   (Integer showing the number of solutions)        +
+//            - WellDone (Boolean showing success or failure of the algo) +
 //=========================================================================
 
    WellDone = Standard_False;
diff --git a/src/GccAna/GccAna_Circ2dTanCen.hxx b/src/GccAna/GccAna_Circ2dTanCen.hxx
index 08c57854d3..7811f49d4e 100644
--- a/src/GccAna/GccAna_Circ2dTanCen.hxx
+++ b/src/GccAna/GccAna_Circ2dTanCen.hxx
@@ -53,7 +53,7 @@ class gp_Circ2d;
 //! We want to create a circle tangent to an EnclosedCirc C1
 //! with a tolerance Tolerance.
 //! If we did not used Tolerance it is impossible to
-//! find a solution in the the following case : Pcenter is
+//! find a solution in the following case : Pcenter is
 //! outside C1.
 //! With Tolerance we will give a solution if the distance
 //! between C1 and Pcenter is lower than or equal Tolerance.
@@ -75,7 +75,7 @@ public:
   Standard_EXPORT GccAna_Circ2dTanCen(const gp_Lin2d& Linetan, const gp_Pnt2d& Pcenter);
   
   //! This method implements the algorithms used to
-  //! create 2d circles passing thrue a point and
+  //! create 2d circles passing through a point and
   //! centered on a point.
   //! Tolerance is a tolerance criterion used by the algorithm
   //! to find a solution when, mathematically, the problem
diff --git a/src/GccAna/GccAna_Circ2dTanOnRad.hxx b/src/GccAna/GccAna_Circ2dTanOnRad.hxx
index 19a0ba4fa3..a60b904e66 100644
--- a/src/GccAna/GccAna_Circ2dTanOnRad.hxx
+++ b/src/GccAna/GccAna_Circ2dTanOnRad.hxx
@@ -55,7 +55,7 @@ class gp_Circ2d;
 //! centered on a line OnLine with a radius Radius and with
 //! a tolerance Tolerance.
 //! If we did not use Tolerance it is impossible to
-//! find a solution in the the following case : OnLine is
+//! find a solution in the following case : OnLine is
 //! outside C1. There is no intersection point between C1
 //! and OnLine. The distance between the line and the
 //! circle is greater than Radius.
diff --git a/src/GccAna/GccAna_Lin2d2Tan.hxx b/src/GccAna/GccAna_Lin2d2Tan.hxx
index d72bc882f2..8499da9921 100644
--- a/src/GccAna/GccAna_Lin2d2Tan.hxx
+++ b/src/GccAna/GccAna_Lin2d2Tan.hxx
@@ -60,14 +60,14 @@ public:
 
   
   //! This methods implements the algorithms used to
-  //! create 2d lines passing thrue 2 points.
+  //! create 2d lines passing through 2 points.
   //! Tolerance is used because we can't create a line
   //! when the distance between the two points is too small.
   Standard_EXPORT GccAna_Lin2d2Tan(const gp_Pnt2d& ThePoint1, const gp_Pnt2d& ThePoint2, const Standard_Real Tolerance);
   
   //! This methods implements the algorithms used to
   //! create 2d lines tangent to one circle and passing
-  //! thrue a point.
+  //! through a point.
   //! Exception BadQualifier is raised in the case of
   //! EnclosedCirc
   //! Tolerance is used because there is no solution
diff --git a/src/GccAna/GccAna_Lin2dTanPar.hxx b/src/GccAna/GccAna_Lin2dTanPar.hxx
index ad626c1f00..854d9b3eb9 100644
--- a/src/GccAna/GccAna_Lin2dTanPar.hxx
+++ b/src/GccAna/GccAna_Lin2dTanPar.hxx
@@ -103,7 +103,7 @@ public:
   //! solution curv.
   //! ParArg is the intrinsic parameter of the point on the
   //! argument curv.
-  //! ParArg is equal 0 when the solution is passing thrue
+  //! ParArg is equal 0 when the solution is passing through
   //! a point. Raises NotDone if the construction algorithm
   //! didn't succeed.
   //! It raises OutOfRange if Index is greater than the
diff --git a/src/Geom/Geom_Curve.hxx b/src/Geom/Geom_Curve.hxx
index 73dc8d243f..2a72409d07 100644
--- a/src/Geom/Geom_Curve.hxx
+++ b/src/Geom/Geom_Curve.hxx
@@ -137,7 +137,7 @@ public:
   //! Some Curves such as OffsetCurve can be closed or not. These curves
   //! are considered as closed if the distance between the first point
   //! and the last point of the curve is lower or equal to the Resolution
-  //! from package gp which is a fixed criterion independant of the
+  //! from package gp which is a fixed criterion independent of the
   //! application.
   Standard_EXPORT virtual Standard_Boolean IsClosed() const = 0;
   
diff --git a/src/Geom/Geom_Transformation.hxx b/src/Geom/Geom_Transformation.hxx
index f78f0b967c..04d127a1d9 100644
--- a/src/Geom/Geom_Transformation.hxx
+++ b/src/Geom/Geom_Transformation.hxx
@@ -152,12 +152,12 @@ public:
   //! Raised if  Row < 1 or Row > 3  or  Col < 1 or Col > 4
   Standard_Real Value (const Standard_Integer theRow, const Standard_Integer theCol) const { return gpTrsf.Value (theRow, theCol); }
 
-  //! Raised if the the transformation is singular. This means that
+  //! Raised if the transformation is singular. This means that
   //! the ScaleFactor is lower or equal to Resolution from
   //! package gp.
   void Invert() { gpTrsf.Invert(); }
 
-  //! Raised if the the transformation is singular. This means that
+  //! Raised if the transformation is singular. This means that
   //! the ScaleFactor is lower or equal to Resolution from
   //! package gp.
   Standard_NODISCARD Standard_EXPORT Handle(Geom_Transformation) Inverted() const;
diff --git a/src/Geom2d/Geom2d_Curve.hxx b/src/Geom2d/Geom2d_Curve.hxx
index 49516a75c5..613fe7df54 100644
--- a/src/Geom2d/Geom2d_Curve.hxx
+++ b/src/Geom2d/Geom2d_Curve.hxx
@@ -131,7 +131,7 @@ public:
   //! Some Curves such as OffsetCurve can be closed or not. These curves
   //! are considered as closed if the distance between the first point
   //! and the last point of the curve is lower or equal to the Resolution
-  //! from package gp which is a fixed criterion independant of the
+  //! from package gp which is a fixed criterion independent of the
   //! application.
   Standard_EXPORT virtual Standard_Boolean IsClosed() const = 0;
   
diff --git a/src/Geom2d/Geom2d_Transformation.hxx b/src/Geom2d/Geom2d_Transformation.hxx
index 4b9f1d0eef..7085b89827 100644
--- a/src/Geom2d/Geom2d_Transformation.hxx
+++ b/src/Geom2d/Geom2d_Transformation.hxx
@@ -162,13 +162,13 @@ public:
   //! Computes the inverse of this transformation.
   //! and  assigns the result to this transformatio
   //!
-  //! Raised if the the transformation is singular. This means that
+  //! Raised if the transformation is singular. This means that
   //! the ScaleFactor is lower or equal to Resolution from
   //! package gp.
   Standard_EXPORT void Invert();
   
   //! Computes the inverse of this transformation and creates a new one.
-  //! Raises ConstructionError  if the the transformation is singular. This means that
+  //! Raises ConstructionError  if the transformation is singular. This means that
   //! the ScaleFactor is lower or equal to Resolution from package gp.
   Standard_NODISCARD Standard_EXPORT Handle(Geom2d_Transformation) Inverted() const;
   
diff --git a/src/Geom2dGcc/Geom2dGcc_Circ2d2TanRad.hxx b/src/Geom2dGcc/Geom2dGcc_Circ2d2TanRad.hxx
index e6c812698e..cb1cbf1a86 100644
--- a/src/Geom2dGcc/Geom2dGcc_Circ2d2TanRad.hxx
+++ b/src/Geom2dGcc/Geom2dGcc_Circ2d2TanRad.hxx
@@ -57,7 +57,7 @@ class gp_Pnt2d;
 //! inside a curve Cu2 with a radius Radius and a
 //! tolerance Tolerance.
 //! If we did not used Tolerance it is impossible to
-//! find a solution in the the following case : Cu2 is
+//! find a solution in the following case : Cu2 is
 //! inside C1 and there is no intersection point
 //! between the two elements.
 //! with Tolerance we will give a solution if the
diff --git a/src/Geom2dGcc/Geom2dGcc_Circ2dTanCen.hxx b/src/Geom2dGcc/Geom2dGcc_Circ2dTanCen.hxx
index d7bb82eb65..e6531240b4 100644
--- a/src/Geom2dGcc/Geom2dGcc_Circ2dTanCen.hxx
+++ b/src/Geom2dGcc/Geom2dGcc_Circ2dTanCen.hxx
@@ -52,7 +52,7 @@ class gp_Pnt2d;
 //! We want to create a circle tangent to an EnclosedCurv C1
 //! with a tolerance Tolerance.
 //! If we did not used Tolerance it is impossible to
-//! find a solution in the the following case : Pcenter is
+//! find a solution in the following case : Pcenter is
 //! outside C1.
 //! With Tolerance we will give a solution if the distance
 //! between C1 and Pcenter is lower than or equal Tolerance/2.
diff --git a/src/Geom2dGcc/Geom2dGcc_Circ2dTanOnRad.hxx b/src/Geom2dGcc/Geom2dGcc_Circ2dTanOnRad.hxx
index f6f831a078..4199bd7017 100644
--- a/src/Geom2dGcc/Geom2dGcc_Circ2dTanOnRad.hxx
+++ b/src/Geom2dGcc/Geom2dGcc_Circ2dTanOnRad.hxx
@@ -58,7 +58,7 @@ class gp_Pnt2d;
 //! centered on a line OnLine with a radius Radius and with
 //! a tolerance Tolerance.
 //! If we did not used Tolerance it is impossible to
-//! find a solution in the the following case : OnLine is
+//! find a solution in the following case : OnLine is
 //! outside Cu1. There is no intersection point between Cu1
 //! and OnLine. The distance between the line and the
 //! circle is greater than Radius.
diff --git a/src/Geom2dGcc/Geom2dGcc_FunctionTanCuCuCu.hxx b/src/Geom2dGcc/Geom2dGcc_FunctionTanCuCuCu.hxx
index 689b81f503..9c7ab70bf4 100644
--- a/src/Geom2dGcc/Geom2dGcc_FunctionTanCuCuCu.hxx
+++ b/src/Geom2dGcc/Geom2dGcc_FunctionTanCuCuCu.hxx
@@ -39,7 +39,7 @@ class math_Matrix;
 
 
 //! This abstract class describes a set on N Functions of
-//! M independant variables.
+//! M independent variables.
 class Geom2dGcc_FunctionTanCuCuCu  : public math_FunctionSetWithDerivatives
 {
 public:
diff --git a/src/Geom2dGcc/Geom2dGcc_FunctionTanCuCuOnCu.hxx b/src/Geom2dGcc/Geom2dGcc_FunctionTanCuCuOnCu.hxx
index 57cce7a713..55e5d97694 100644
--- a/src/Geom2dGcc/Geom2dGcc_FunctionTanCuCuOnCu.hxx
+++ b/src/Geom2dGcc/Geom2dGcc_FunctionTanCuCuOnCu.hxx
@@ -41,7 +41,7 @@ class math_Matrix;
 
 
 //! This abstract class describes a set on N Functions of
-//! M independant variables.
+//! M independent variables.
 class Geom2dGcc_FunctionTanCuCuOnCu  : public math_FunctionSetWithDerivatives
 {
 public:
diff --git a/src/Geom2dGcc/Geom2dGcc_Lin2d2TanIter.hxx b/src/Geom2dGcc/Geom2dGcc_Lin2d2TanIter.hxx
index 125f5cb157..5dfb420336 100644
--- a/src/Geom2dGcc/Geom2dGcc_Lin2d2TanIter.hxx
+++ b/src/Geom2dGcc/Geom2dGcc_Lin2d2TanIter.hxx
@@ -58,7 +58,7 @@ public:
   Standard_EXPORT Geom2dGcc_Lin2d2TanIter(const Geom2dGcc_QCurve& Qualified1, const gp_Pnt2d& ThePoint, const Standard_Real Param1, const Standard_Real Tolang);
   
   //! This class implements the algorithms used to create 2d
-  //! line tangent to a circle and to a cuve.
+  //! line tangent to a circle and to a curve.
   //! Tolang is used to determine the tolerance for the
   //! tangency points.
   //! Param2 is used for the initial guess on the curve.
diff --git a/src/Geom2dInt/Geom2dInt_TheLocateExtPCOfTheProjPCurOfGInter.hxx b/src/Geom2dInt/Geom2dInt_TheLocateExtPCOfTheProjPCurOfGInter.hxx
index 8bb0e9fae1..56f5200057 100644
--- a/src/Geom2dInt/Geom2dInt_TheLocateExtPCOfTheProjPCurOfGInter.hxx
+++ b/src/Geom2dInt/Geom2dInt_TheLocateExtPCOfTheProjPCurOfGInter.hxx
@@ -46,7 +46,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! TolU is used to decide to stop the iterations.
   //! At the nth iteration, the criteria is:
@@ -57,7 +57,7 @@ public:
   //! The close point is defined by the parameter value
   //! U0.
   //! The function F(u)=distance(P,C(u)) has an extremum
-  //! when g(u)=dF/du=0. The algorithm searchs a zero
+  //! when g(u)=dF/du=0. The algorithm searches a zero
   //! near the close point.
   //! Zeros are searched between Umin et Usup.
   //! TolU is used to decide to stop the iterations.
diff --git a/src/Geom2dInt/Geom2dInt_ThePolygon2dOfTheIntPCurvePCurveOfGInter.hxx b/src/Geom2dInt/Geom2dInt_ThePolygon2dOfTheIntPCurvePCurveOfGInter.hxx
index 8dcaffc205..de9c6a78f2 100644
--- a/src/Geom2dInt/Geom2dInt_ThePolygon2dOfTheIntPCurvePCurveOfGInter.hxx
+++ b/src/Geom2dInt/Geom2dInt_ThePolygon2dOfTheIntPCurvePCurveOfGInter.hxx
@@ -48,7 +48,7 @@ public:
   Standard_EXPORT Geom2dInt_ThePolygon2dOfTheIntPCurvePCurveOfGInter(const Adaptor2d_Curve2d& Curve, const Standard_Integer NbPnt, const IntRes2d_Domain& Domain, const Standard_Real Tol);
   
   //! The current polygon is modified if most
-  //! of the  points of the  polygon  are are
+  //! of the  points of the  polygon  are
   //! outside  the  box  <OtherBox>.  In this
   //! situation, bounds are computed to build
   //! a polygon inside or near the OtherBox.
diff --git a/src/Geom2dInt/Geom2dInt_TheProjPCurOfGInter.hxx b/src/Geom2dInt/Geom2dInt_TheProjPCurOfGInter.hxx
index 21068956ba..63671301ef 100644
--- a/src/Geom2dInt/Geom2dInt_TheProjPCurOfGInter.hxx
+++ b/src/Geom2dInt/Geom2dInt_TheProjPCurOfGInter.hxx
@@ -40,7 +40,7 @@ public:
   
   //! Returns the parameter V of the point on the
   //! parametric curve corresponding to the Point Pnt.
-  //! The Correspondance between Pnt and the point P(V)
+  //! The Correspondence between Pnt and the point P(V)
   //! on the parametric curve must be coherent with the
   //! way of determination of the signed distance
   //! between a point and the implicit curve.
@@ -53,7 +53,7 @@ public:
   
   //! Returns the parameter V of the point on the
   //! parametric curve corresponding to the Point Pnt.
-  //! The Correspondance between Pnt and the point P(V)
+  //! The Correspondence between Pnt and the point P(V)
   //! on the parametric curve must be coherent with the
   //! way of determination of the signed distance
   //! between a point and the implicit curve.
diff --git a/src/Geom2dLProp/Geom2dLProp_NumericCurInf2d.hxx b/src/Geom2dLProp/Geom2dLProp_NumericCurInf2d.hxx
index edc98a3d2e..cf7472ec5f 100644
--- a/src/Geom2dLProp/Geom2dLProp_NumericCurInf2d.hxx
+++ b/src/Geom2dLProp/Geom2dLProp_NumericCurInf2d.hxx
@@ -45,11 +45,11 @@ public:
   Standard_EXPORT void PerformInf (const Handle(Geom2d_Curve)& C, LProp_CurAndInf& Result);
   
   //! Computes the locals extremas of curvature.
-  //! in the interval of parmeters [UMin,UMax].
+  //! in the interval of parameters [UMin,UMax].
   Standard_EXPORT void PerformCurExt (const Handle(Geom2d_Curve)& C, const Standard_Real UMin, const Standard_Real UMax, LProp_CurAndInf& Result);
   
   //! Computes the inflections in the interval of
-  //! parmeters [UMin,UMax].
+  //! parameters [UMin,UMax].
   Standard_EXPORT void PerformInf (const Handle(Geom2d_Curve)& C, const Standard_Real UMin, const Standard_Real UMax, LProp_CurAndInf& Result);
   
   //! True if the solutions are found.
diff --git a/src/GeomFill/GeomFill_GuideTrihedronAC.cxx b/src/GeomFill/GeomFill_GuideTrihedronAC.cxx
index 7f197c9a0f..909bee101b 100644
--- a/src/GeomFill/GeomFill_GuideTrihedronAC.cxx
+++ b/src/GeomFill/GeomFill_GuideTrihedronAC.cxx
@@ -13,7 +13,7 @@
 // Alternatively, this file may be used under the terms of Open CASCADE
 // commercial license or contractual agreement.
 
-// Creted:	Tue Jun 23 15:39:24 1998
+// Created:	Tue Jun 23 15:39:24 1998
 
 #include <Adaptor3d_Curve.hxx>
 #include <Approx_CurvlinFunc.hxx>
diff --git a/src/GeomFill/GeomFill_GuideTrihedronAC.hxx b/src/GeomFill/GeomFill_GuideTrihedronAC.hxx
index 08e7c58f17..0642cbcc30 100644
--- a/src/GeomFill/GeomFill_GuideTrihedronAC.hxx
+++ b/src/GeomFill/GeomFill_GuideTrihedronAC.hxx
@@ -84,7 +84,7 @@ public:
   Standard_EXPORT virtual Standard_Boolean IsConstant() const Standard_OVERRIDE;
   
   //! Say if the law is defined, only by the 3d Geometry of
-  //! the setted Curve
+  //! the set Curve
   //! Return False by Default.
   Standard_EXPORT virtual Standard_Boolean IsOnlyBy3dCurve() const Standard_OVERRIDE;
   
diff --git a/src/GeomFill/GeomFill_GuideTrihedronPlan.hxx b/src/GeomFill/GeomFill_GuideTrihedronPlan.hxx
index bd670ed3ce..acd01c5814 100644
--- a/src/GeomFill/GeomFill_GuideTrihedronPlan.hxx
+++ b/src/GeomFill/GeomFill_GuideTrihedronPlan.hxx
@@ -92,7 +92,7 @@ public:
   Standard_EXPORT virtual Standard_Boolean IsConstant() const Standard_OVERRIDE;
   
   //! Say if the law is defined, only by the 3d Geometry of
-  //! the setted Curve
+  //! the set Curve
   //! Return False by Default.
   Standard_EXPORT virtual Standard_Boolean IsOnlyBy3dCurve() const Standard_OVERRIDE;
   
diff --git a/src/GeomFill/GeomFill_LocationGuide.cxx b/src/GeomFill/GeomFill_LocationGuide.cxx
index 81848896c3..d364fa727c 100644
--- a/src/GeomFill/GeomFill_LocationGuide.cxx
+++ b/src/GeomFill/GeomFill_LocationGuide.cxx
@@ -218,7 +218,7 @@ static void InGoodPeriod(const Standard_Real Prec,
 {
   if (myCurve.IsNull())
     throw Standard_ConstructionError(
-          "GeomFill_LocationGuide::The path is not setted !!");
+          "GeomFill_LocationGuide::The path is not set !!");
 
     //repere fixe
   gp_Ax3 Rep(gp::Origin(), gp::DZ(), gp::DX());
diff --git a/src/GeomFill/GeomFill_Pipe.hxx b/src/GeomFill/GeomFill_Pipe.hxx
index ff2d0721a5..0679fe099b 100644
--- a/src/GeomFill/GeomFill_Pipe.hxx
+++ b/src/GeomFill/GeomFill_Pipe.hxx
@@ -65,10 +65,10 @@ class gp_Dir;
 //! It is useful to keep a constant angle between
 //! input surface and the pipe.                           --
 //! 3) give a  path and two sections. The section
-//! evoluate from First to Last Section.
+//! evaluate from First to Last Section.
 //!
 //! 3) give a  path and N sections. The section
-//! evoluate from First to Last Section.
+//! evaluate from First to Last Section.
 //!
 //! In general case the result is a NURBS. But we
 //! can  generate plane,  cylindrical, spherical,
@@ -113,11 +113,11 @@ public:
   Standard_EXPORT GeomFill_Pipe(const Handle(Geom_Curve)& Path, const Handle(Geom_Curve)& FirstSect, const gp_Dir& Dir);
   
   //! Create a pipe with an evolving section
-  //! The section evoluate from First to Last Section
+  //! The section evaluate from First to Last Section
   Standard_EXPORT GeomFill_Pipe(const Handle(Geom_Curve)& Path, const Handle(Geom_Curve)& FirstSect, const Handle(Geom_Curve)& LastSect);
   
   //! Create a pipe with N  sections
-  //! The section evoluate from First to Last Section
+  //! The section evaluate from First to Last Section
   Standard_EXPORT GeomFill_Pipe(const Handle(Geom_Curve)& Path, const TColGeom_SequenceOfCurve& NSections);
   
   //! Create  a pipe  with  a constant  radius with  2
diff --git a/src/GeomFill/GeomFill_Sweep.hxx b/src/GeomFill/GeomFill_Sweep.hxx
index 7bf92b3fad..2a7b506d17 100644
--- a/src/GeomFill/GeomFill_Sweep.hxx
+++ b/src/GeomFill/GeomFill_Sweep.hxx
@@ -105,7 +105,7 @@ public:
   //! Segmax     : The maximum number of span in v required on
   //! the surface
   //!
-  //! raise If Domain are infinite or Profile not Setted.
+  //! raise If Domain are infinite or Profile not set.
   Standard_EXPORT void Build (const Handle(GeomFill_SectionLaw)& Section, const GeomFill_ApproxStyle Methode = GeomFill_Location, const GeomAbs_Shape Continuity = GeomAbs_C2, const Standard_Integer Degmax = 10, const Standard_Integer Segmax = 30);
   
   //! Tells if the Surface is Buildt.
diff --git a/src/GeomFill/GeomFill_SweepSectionGenerator.hxx b/src/GeomFill/GeomFill_SweepSectionGenerator.hxx
index fc2096f6c4..991a828440 100644
--- a/src/GeomFill/GeomFill_SweepSectionGenerator.hxx
+++ b/src/GeomFill/GeomFill_SweepSectionGenerator.hxx
@@ -51,7 +51,7 @@ public:
   Standard_EXPORT GeomFill_SweepSectionGenerator(const Handle(Geom_Curve)& Path, const Handle(Geom_Curve)& FirstSect);
   
   //! Create a sweept surface with an evolving section
-  //! The section evoluate from First to Last Section
+  //! The section evaluate from First to Last Section
   Standard_EXPORT GeomFill_SweepSectionGenerator(const Handle(Geom_Curve)& Path, const Handle(Geom_Curve)& FirstSect, const Handle(Geom_Curve)& LastSect);
   
   //! Create  a pipe  with  a constant  radius with  2
diff --git a/src/GeomFill/GeomFill_TrihedronLaw.hxx b/src/GeomFill/GeomFill_TrihedronLaw.hxx
index d504c04a73..4cba026728 100644
--- a/src/GeomFill/GeomFill_TrihedronLaw.hxx
+++ b/src/GeomFill/GeomFill_TrihedronLaw.hxx
@@ -88,7 +88,7 @@ public:
   Standard_EXPORT virtual Standard_Boolean IsConstant() const;
   
   //! Say if the law is defined, only by the 3d Geometry of
-  //! the setted Curve
+  //! the set Curve
   //! Return False by Default.
   Standard_EXPORT virtual Standard_Boolean IsOnlyBy3dCurve() const;
 
diff --git a/src/GeomInt/GeomInt_LineTool.cxx b/src/GeomInt/GeomInt_LineTool.cxx
index de5b9a8147..f33fedb3f9 100644
--- a/src/GeomInt/GeomInt_LineTool.cxx
+++ b/src/GeomInt/GeomInt_LineTool.cxx
@@ -838,7 +838,7 @@ Standard_Boolean GeomInt_LineTool::
 
       if(!bIsFirstInside && !bIsLastInside) {
 	if((ifprm < aListOfIndex.First()) && (ilprm > aListOfIndex.Last())) {
-	  // append whole line, and boundaries if neccesary
+	  // append whole line, and boundaries if necessary
 	  if(bhasfirstpoint) {
 	    const IntSurf_PntOn2S& aP = aSeqOfPntOn2S->Value(aListOfFLIndex.First());
 	    aLineOn2S->Add(aP);
diff --git a/src/GeomLib/GeomLib_CheckCurveOnSurface.cxx b/src/GeomLib/GeomLib_CheckCurveOnSurface.cxx
index a282ce2a60..65c6dbe6dd 100644
--- a/src/GeomLib/GeomLib_CheckCurveOnSurface.cxx
+++ b/src/GeomLib/GeomLib_CheckCurveOnSurface.cxx
@@ -122,7 +122,7 @@ class GeomLib_CheckCurveOnSurface_TargetFunc :
     return Derive(theX(1), theGrad(1));
   }
 
-  //returns 1st derivative of the the one-dimension-function when
+  //returns 1st derivative of the one-dimension-function when
   //parameter is equal to theX
   Standard_Boolean Derive(const Standard_Real theX, Standard_Real& theDeriv1, Standard_Real* const theDeriv2 = 0) const
   {
diff --git a/src/GeomPlate/GeomPlate_BuildPlateSurface.hxx b/src/GeomPlate/GeomPlate_BuildPlateSurface.hxx
index 3e35bf25d5..72c9d4e837 100644
--- a/src/GeomPlate/GeomPlate_BuildPlateSurface.hxx
+++ b/src/GeomPlate/GeomPlate_BuildPlateSurface.hxx
@@ -155,7 +155,7 @@ public:
 
   //! Allows you to ensure that the array of curves returned by
   //! Curves2d has the correct orientation. Returns the
-  //! orientation of the curves in the the array returned by
+  //! orientation of the curves in the array returned by
   //! Curves2d. Computation changes the orientation of
   //! these curves. Consequently, this method returns the
   //! orientation prior to computation.
diff --git a/src/GeometryTest/GeometryTest_SurfaceCommands.cxx b/src/GeometryTest/GeometryTest_SurfaceCommands.cxx
index 4854be844c..58a0a620ba 100644
--- a/src/GeometryTest/GeometryTest_SurfaceCommands.cxx
+++ b/src/GeometryTest/GeometryTest_SurfaceCommands.cxx
@@ -408,7 +408,7 @@ void  GeometryTest::SurfaceCommands(Draw_Interpretor& theCommands)
 		  __FILE__,
 		  tuyau,g);
 
-  theCommands.Add("sweep", "sweep result [options] path [Surf] curve [Tol [nbsegment]]\n sweep the the curve along the path, options are \n -FX : Tangent and Normal are fixed\n -FR : Tangent and Normal are given by Frenet trihedron \n -CF : Tangente is given by Frenet, \n     the Normal is computed to minimize the torsion \n -DX : Tangent and Normal are given by Darboux trihedron \n     <path> have to be a 2d curve,\n     <Surf> have to be defined\n -CN dx dy dz : Normal is given by dx dy dz" ,
+  theCommands.Add("sweep", "sweep result [options] path [Surf] curve [Tol [nbsegment]]\n sweep the curve along the path, options are \n -FX : Tangent and Normal are fixed\n -FR : Tangent and Normal are given by Frenet trihedron \n -CF : Tangente is given by Frenet, \n     the Normal is computed to minimize the torsion \n -DX : Tangent and Normal are given by Darboux trihedron \n     <path> have to be a 2d curve,\n     <Surf> have to be defined\n -CN dx dy dz : Normal is given by dx dy dz" ,
 		  __FILE__,
 		  sweep, g);
 
diff --git a/src/Graphic3d/Graphic3d_CView.hxx b/src/Graphic3d/Graphic3d_CView.hxx
index 07f48f47cb..639f8875df 100644
--- a/src/Graphic3d/Graphic3d_CView.hxx
+++ b/src/Graphic3d/Graphic3d_CView.hxx
@@ -367,7 +367,7 @@ public:
   //! Returns background image texture map.
   virtual Handle(Graphic3d_TextureMap) BackgroundImage() = 0;
 
-  //! Sets image texture or environment cubemap as backround.
+  //! Sets image texture or environment cubemap as background.
   //! @param theTextureMap [in] source to set a background;
   //!                           should be either Graphic3d_Texture2D or Graphic3d_CubeMap
   //! @param theToUpdatePBREnv [in] defines whether IBL maps will be generated or not
@@ -381,7 +381,7 @@ public:
   //! Sets background image fill style.
   virtual void SetBackgroundImageStyle (const Aspect_FillMethod theFillStyle) = 0;
 
-  //! Returns cubemap being setted last time on background.
+  //! Returns cubemap being set last time on background.
   virtual Handle(Graphic3d_CubeMap) BackgroundCubeMap() const = 0;
 
   //! Generates PBR specular probe and irradiance map
diff --git a/src/Graphic3d/Graphic3d_CubeMapSeparate.hxx b/src/Graphic3d/Graphic3d_CubeMapSeparate.hxx
index 74f72c5037..17504a4241 100644
--- a/src/Graphic3d/Graphic3d_CubeMapSeparate.hxx
+++ b/src/Graphic3d/Graphic3d_CubeMapSeparate.hxx
@@ -29,7 +29,7 @@ public:
   //! @thePaths - array of paths to separate image files (has to have size equal 6).
   Standard_EXPORT Graphic3d_CubeMapSeparate (const NCollection_Array1<TCollection_AsciiString>& thePaths);
 
-  //! Initializes cubemap to be setted directly from PixMaps.
+  //! Initializes cubemap to be set directly from PixMaps.
   //! @theImages - array if PixMaps (has to have size equal 6).
   Standard_EXPORT Graphic3d_CubeMapSeparate(const NCollection_Array1<Handle(Image_PixMap)>& theImages);
 
diff --git a/src/Graphic3d/Graphic3d_Group.hxx b/src/Graphic3d/Graphic3d_Group.hxx
index fb6748302e..a49c6d4d18 100644
--- a/src/Graphic3d/Graphic3d_Group.hxx
+++ b/src/Graphic3d/Graphic3d_Group.hxx
@@ -76,7 +76,7 @@ class Graphic3d_Group : public Standard_Transient
 
 public:
 
-  //! Supress all primitives and attributes of <me>.
+  //! Suppress all primitives and attributes of <me>.
   //! To clear group without update in Graphic3d_StructureManager
   //! pass Standard_False as <theUpdateStructureMgr>. This
   //! used on context and viewer destruction, when the pointer
@@ -85,10 +85,10 @@ public:
   //! cross-reference);
   Standard_EXPORT virtual void Clear (const Standard_Boolean theUpdateStructureMgr = Standard_True);
 
-  //! Supress the group <me> in the structure.
+  //! Suppress the group <me> in the structure.
   Standard_EXPORT virtual ~Graphic3d_Group();
 
-  //! Supress the group <me> in the structure.
+  //! Suppress the group <me> in the structure.
   //! Warning: No more graphic operations in <me> after this call.
   //! Modifies the current modelling transform persistence (pan, zoom or rotate)
   //! Get the current modelling transform persistence (pan, zoom or rotate)
diff --git a/src/Graphic3d/Graphic3d_MaterialAspect.hxx b/src/Graphic3d/Graphic3d_MaterialAspect.hxx
index e67601deda..497d68be40 100644
--- a/src/Graphic3d/Graphic3d_MaterialAspect.hxx
+++ b/src/Graphic3d/Graphic3d_MaterialAspect.hxx
@@ -28,7 +28,7 @@
 //! Aspect attributes of a 3d face.
 //! Keywords: Material, FillArea, Shininess, Ambient, Color, Diffuse,
 //! Specular, Transparency, Emissive, ReflectionMode,
-//! BackFace, FrontFace, Reflection, Absorbtion
+//! BackFace, FrontFace, Reflection, Absorption
 class Graphic3d_MaterialAspect 
 {
 public:
diff --git a/src/Graphic3d/Graphic3d_ShaderProgram.hxx b/src/Graphic3d/Graphic3d_ShaderProgram.hxx
index b039067329..218d8a4b5d 100755
--- a/src/Graphic3d/Graphic3d_ShaderProgram.hxx
+++ b/src/Graphic3d/Graphic3d_ShaderProgram.hxx
@@ -29,7 +29,7 @@ typedef NCollection_Sequence<Handle(Graphic3d_ShaderObject)> Graphic3d_ShaderObj
 //! List of custom uniform shader variables.
 typedef NCollection_Sequence<Handle(Graphic3d_ShaderVariable)> Graphic3d_ShaderVariableList;
 
-//! List of custom vertex shader attrubures
+//! List of custom vertex shader attributes
 typedef NCollection_Sequence<Handle(Graphic3d_ShaderAttribute)> Graphic3d_ShaderAttributeList;
 
 //! This class is responsible for managing shader programs.
diff --git a/src/Graphic3d/Graphic3d_Structure.hxx b/src/Graphic3d/Graphic3d_Structure.hxx
index 303441a9c1..3eca618adc 100644
--- a/src/Graphic3d/Graphic3d_Structure.hxx
+++ b/src/Graphic3d/Graphic3d_Structure.hxx
@@ -279,7 +279,7 @@ public:
   //! method returns boundaries taking into account infinite state
   //! of the structure. This approach generally used for application
   //! specific fit operation (e.g. fitting the model into screen,
-  //! not taking into accout infinite helper elements).
+  //! not taking into account infinite helper elements).
   //! Warning: If the structure <me> is empty then the empty box is returned,
   //! If the structure <me> is infinite then the whole box is returned.
   Standard_EXPORT Bnd_Box MinMaxValues (const Standard_Boolean theToIgnoreInfiniteFlag = Standard_False) const;
diff --git a/src/Graphic3d/Graphic3d_Texture1Dsegment.hxx b/src/Graphic3d/Graphic3d_Texture1Dsegment.hxx
index 02dc8db815..bc47bffe70 100644
--- a/src/Graphic3d/Graphic3d_Texture1Dsegment.hxx
+++ b/src/Graphic3d/Graphic3d_Texture1Dsegment.hxx
@@ -32,7 +32,7 @@ DEFINE_STANDARD_HANDLE(Graphic3d_Texture1Dsegment, Graphic3d_Texture1D)
 //! This class provides the implementation
 //! of a 1D texture applyable along a segment.
 //! You might use the SetSegment() method
-//! to set the way the texture is "streched" on facets.
+//! to set the way the texture is "stretched" on facets.
 class Graphic3d_Texture1Dsegment : public Graphic3d_Texture1D
 {
 
diff --git a/src/Graphic3d/Graphic3d_TextureRoot.cxx b/src/Graphic3d/Graphic3d_TextureRoot.cxx
index 21ec53ff5a..5911201b38 100644
--- a/src/Graphic3d/Graphic3d_TextureRoot.cxx
+++ b/src/Graphic3d/Graphic3d_TextureRoot.cxx
@@ -74,10 +74,10 @@ TCollection_AsciiString Graphic3d_TextureRoot::TexturesFolder()
     if (!aDir.Exists() || !aTextureFile.Exists())
     {
 #ifdef OCCT_DEBUG
-      std::cerr << " CSF_MDTVTexturesDirectory or CASROOT not correctly setted\n";
+      std::cerr << " CSF_MDTVTexturesDirectory or CASROOT not correctly set\n";
       std::cerr << " not all files are found in : "<< VarName.ToCString() << std::endl;
 #endif
-      throw Standard_Failure("CSF_MDTVTexturesDirectory or CASROOT not correctly setted");
+      throw Standard_Failure("CSF_MDTVTexturesDirectory or CASROOT not correctly set");
     }
   }
   return VarName;
diff --git a/src/Graphic3d/Graphic3d_TypeOfLimit.hxx b/src/Graphic3d/Graphic3d_TypeOfLimit.hxx
index 4cb85fcc0a..3b501ae535 100644
--- a/src/Graphic3d/Graphic3d_TypeOfLimit.hxx
+++ b/src/Graphic3d/Graphic3d_TypeOfLimit.hxx
@@ -35,7 +35,7 @@ enum Graphic3d_TypeOfLimit
   Graphic3d_TypeOfLimit_HasBlendedOitMsaa,              //!< indicates whether necessary GL extensions for Weighted, Blended OIT available (with MSAA).
   Graphic3d_TypeOfLimit_HasFlatShading,                 //!< indicates whether Flat shading (Graphic3d_TOSM_FACET) is supported
   Graphic3d_TypeOfLimit_HasMeshEdges,                   //!< indicates whether advanced mesh edges presentation is supported
-  Graphic3d_TypeOfLimit_IsWorkaroundFBO,                //!< indicates whether workaround for Intel driver problem with empty FBO for images with big width is applyed.
+  Graphic3d_TypeOfLimit_IsWorkaroundFBO,                //!< indicates whether workaround for Intel driver problem with empty FBO for images with big width is applied.
   Graphic3d_TypeOfLimit_NB                              //!< number of elements in this enumeration
 };
 
diff --git a/src/gce/gce_MakeParab2d.hxx b/src/gce/gce_MakeParab2d.hxx
index 3a5cdef83e..edc2e81cc5 100644
--- a/src/gce/gce_MakeParab2d.hxx
+++ b/src/gce/gce_MakeParab2d.hxx
@@ -54,7 +54,7 @@ class gp_Parab2d;
 //! * Create a Parab2d from one apex  and the center.
 //! * Create a Parab2d with the directrix and the focus point.
 //! * Create a Parab2d with its vertex point and its axis
-//! of symetry and its focus length.
+//! of symmetry and its focus length.
 class gce_MakeParab2d  : public gce_Root
 {
 public:
diff --git a/src/gp/gp_Dir2d.hxx b/src/gp/gp_Dir2d.hxx
index d775029c24..17fbde6832 100644
--- a/src/gp/gp_Dir2d.hxx
+++ b/src/gp/gp_Dir2d.hxx
@@ -182,7 +182,7 @@ public:
     Standard_Boolean IsOpposite (const gp_Dir2d& Other, const Standard_Real AngularTolerance) const;
   
 
-  //! returns true if if the angle between this unit vector and unit
+  //! returns true if the angle between this unit vector and unit
   //! vector Other is equal to 0, Pi or -Pi.
   //! i.e.  Abs(Angle(<me>, Other)) <= AngularTolerance or
   //! PI - Abs(Angle(<me>, Other)) <= AngularTolerance
diff --git a/src/gp/gp_Hypr.hxx b/src/gp/gp_Hypr.hxx
index aaaa3046ac..0be01c5c23 100644
--- a/src/gp/gp_Hypr.hxx
+++ b/src/gp/gp_Hypr.hxx
@@ -181,7 +181,7 @@ public:
     gp_Ax1 Directrix2() const;
   
 
-  //! Returns the excentricity of the hyperbola (e > 1).
+  //! Returns the eccentricity of the hyperbola (e > 1).
   //! If f is the distance between the location of the hyperbola
   //! and the Focus1 then the eccentricity e = f / MajorRadius. Raises DomainError if MajorRadius = 0.0
     Standard_Real Eccentricity() const;
diff --git a/src/gp/gp_Hypr2d.hxx b/src/gp/gp_Hypr2d.hxx
index 220ca926d0..ae69a6bb5e 100644
--- a/src/gp/gp_Hypr2d.hxx
+++ b/src/gp/gp_Hypr2d.hxx
@@ -195,7 +195,7 @@ public:
     gp_Ax2d Directrix2() const;
   
 
-  //! Returns the excentricity of the hyperbola (e > 1).
+  //! Returns the eccentricity of the hyperbola (e > 1).
   //! If f is the distance between the location of the hyperbola
   //! and the Focus1 then the eccentricity e = f / MajorRadius. Raises DomainError if MajorRadius = 0.0.
     Standard_Real Eccentricity() const;
diff --git a/src/gp/gp_Mat.hxx b/src/gp/gp_Mat.hxx
index 8eb57bc987..b3b090c329 100644
--- a/src/gp/gp_Mat.hxx
+++ b/src/gp/gp_Mat.hxx
@@ -103,7 +103,7 @@ public:
   Standard_EXPORT void SetRows (const gp_XYZ& Row1, const gp_XYZ& Row2, const gp_XYZ& Row3);
   
 
-  //! Modifies the the matrix so that it represents
+  //! Modifies the matrix so that it represents
   //! a scaling transformation, where S is the scale factor. :
   //! | S    0.0  0.0 |
   //! <me> =  | 0.0   S   0.0 |
diff --git a/src/gp/gp_XYZ.hxx b/src/gp/gp_XYZ.hxx
index 99dbb1ce0b..0612f5455f 100644
--- a/src/gp/gp_XYZ.hxx
+++ b/src/gp/gp_XYZ.hxx
@@ -45,7 +45,7 @@ public:
   DEFINE_STANDARD_ALLOC
 
   
-  //! Creates an XYZ object with zero co-ordinates (0,0,0)
+  //! Creates an XYZ object with zero coordinates (0,0,0)
     gp_XYZ();
   
   //! creates an XYZ with given coordinates