diff --git a/Boolean_set_operations_2/examples/Boolean_set_operations_2/bezier_traits_adapter2.cpp b/Boolean_set_operations_2/examples/Boolean_set_operations_2/bezier_traits_adapter2.cpp
index 2c5b160b40a..853340f86d2 100644
--- a/Boolean_set_operations_2/examples/Boolean_set_operations_2/bezier_traits_adapter2.cpp
+++ b/Boolean_set_operations_2/examples/Boolean_set_operations_2/bezier_traits_adapter2.cpp
@@ -168,11 +168,11 @@ bool read_bezier(char const* aFileName, Bezier_polygon_set& rSet)
       }
     }
     catch(std::exception const& x) {
-      std::cout << "An exception ocurred during reading of Bezier polygon set:"
+      std::cout << "An exception occurred during reading of Bezier polygon set:"
                 << x.what() << std::endl;
     }
     catch(...) {
-      std::cout << "An exception ocurred during reading of Bezier polygon set."
+      std::cout << "An exception occurred during reading of Bezier polygon set."
                 << std::endl;
     }
   }
diff --git a/Polyline_simplification_2/demo/Polyline_simplification_2/Polyline_simplification_2.cpp b/Polyline_simplification_2/demo/Polyline_simplification_2/Polyline_simplification_2.cpp
index 987b924dcee..67a8026f17f 100644
--- a/Polyline_simplification_2/demo/Polyline_simplification_2/Polyline_simplification_2.cpp
+++ b/Polyline_simplification_2/demo/Polyline_simplification_2/Polyline_simplification_2.cpp
@@ -321,7 +321,7 @@ void MainWindow::on_actionSimplify_triggered()
   }
   catch(...)
   {
-    statusBar()->showMessage(QString("Exception ocurred"));
+    statusBar()->showMessage(QString("Exception occurred"));
   }
 
    // default cursor
@@ -478,7 +478,7 @@ void MainWindow::loadOSM(QString fileName)
   }
   catch(...)
   {
-    statusBar()->showMessage(QString("Exception ocurred"));
+    statusBar()->showMessage(QString("Exception occurred"));
   }
 
   Q_EMIT( changed());
diff --git a/Straight_skeleton_2/include/CGAL/Straight_skeleton_2/Straight_skeleton_builder_2_impl.h b/Straight_skeleton_2/include/CGAL/Straight_skeleton_2/Straight_skeleton_builder_2_impl.h
index c2abf5e77ca..134230070c7 100644
--- a/Straight_skeleton_2/include/CGAL/Straight_skeleton_2/Straight_skeleton_builder_2_impl.h
+++ b/Straight_skeleton_2/include/CGAL/Straight_skeleton_2/Straight_skeleton_builder_2_impl.h
@@ -367,7 +367,7 @@ void Straight_skeleton_builder_2<Gt,Ss,V>::CollectNewEvents( Vertex_handle aNode
 
 // Handles the special case of two simultaneous edge events, that is, two edges
 // collapsing along the line/point were they meet at the same time.
-// This ocurrs when the bisector emerging from vertex 'aA' is defined by the same pair of
+// This occurs when the bisector emerging from vertex 'aA' is defined by the same pair of
 // contour edges as the bisector emerging from vertex 'aB' (but in opposite order).
 //
 template<class Gt, class Ss, class V>
diff --git a/Straight_skeleton_2/include/CGAL/constructions/Straight_skeleton_cons_ftC2.h b/Straight_skeleton_2/include/CGAL/constructions/Straight_skeleton_cons_ftC2.h
index a391e44029a..3ef15939e8d 100644
--- a/Straight_skeleton_2/include/CGAL/constructions/Straight_skeleton_cons_ftC2.h
+++ b/Straight_skeleton_2/include/CGAL/constructions/Straight_skeleton_cons_ftC2.h
@@ -385,10 +385,10 @@ boost::optional< Point_2<K> > compute_oriented_midpoint ( Segment_2_with_ID<K> c
 // If you ask for the right child point for a trisegment tree corresponding to a split event you will just get e1.target()
 // which is nonsensical for a non initial split event.
 //
-// NOTE: There is an abnormal collinearity case which ocurrs when e0 and e2 are collinear.
+// NOTE: There is an abnormal collinearity case which occurs when e0 and e2 are collinear.
 // In this case, these lines do not correspond to an offset vertex (because e0* and e2* are never consecutive before the event),
 // so the degenerate seed is neither the left or the right seed. In this case, the SEED ID for the degenerate pseudo seed is UNKOWN.
-// If you request the point of such degenerate pseudo seed the oriented midpoint bettwen e0 and e2 is returned.
+// If you request the point of such degenerate pseudo seed the oriented midpoint between e0 and e2 is returned.
 //
 template <class K, class CoeffCache>
 boost::optional< Point_2<K> >
diff --git a/Straight_skeleton_2/include/CGAL/predicates/Straight_skeleton_pred_ftC2.h b/Straight_skeleton_2/include/CGAL/predicates/Straight_skeleton_pred_ftC2.h
index 082968ba60d..34bb01047ae 100644
--- a/Straight_skeleton_2/include/CGAL/predicates/Straight_skeleton_pred_ftC2.h
+++ b/Straight_skeleton_2/include/CGAL/predicates/Straight_skeleton_pred_ftC2.h
@@ -368,7 +368,7 @@ is_edge_facing_offset_lines_isecC2 ( boost::intrusive_ptr< Trisegment_2<K, Segme
 // If the opposite edge is 'e' and its previous/next edges are "preve"/"nexte" then the split point is inside the offset
 // edge if it is NOT to the positive side of [preve,e] *and* NOT to the negative side o [e,nexte].
 // (so this predicate answer half the question, at one and other side independenty).
-// If the split point is exacty over any of this bisectors then the split point ocurres exactly and one (or both) endpoints
+// If the split point is exacty over any of this bisectors then the split point occurs exactly and one (or both) endpoints
 // of the opposite edge (so it is a pseudo-split event since the opposite edge is not itself split in two halfeves)
 // When this predicate is called to test (prev,e), e is the primary edge but since it is  pass as e1, primary_is_0=false.
 // This causes the case of parallel but not collinear edges to return positive when the split point is before the source point of e*