diff --git a/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/CGAL/Arr_counting_traits_2.h b/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/CGAL/Arr_counting_traits_2.h
index 95afeefeaef..ba643bb62de 100644
--- a/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/CGAL/Arr_counting_traits_2.h
+++ b/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/CGAL/Arr_counting_traits_2.h
@@ -14,12 +14,12 @@ namespace CGAL {
 
 /*! \ingroup PkgArrangementOnSurface2TraitsClasses
  *
- * A meradata traits-class decorator for the arrangement package. It counts the
+ * A metadata traits-class decorator for the arrangement package. It counts the
  * number of invocations of traits-class functors. It is parameterized with
  * another traits class and inherits from it. For each traits method it
  * maintains a counter that counts the number of invocations into the method.
  *
- * It models all the concept that the original trais models.
+ * It models all the concepts that the original traits models.
  */
 
 template <typename BaseTraits>
@@ -70,8 +70,7 @@ public:
   template <typename ... Args>
   Arr_counting_traits_2(Args ... args) : Base(std::forward<Args>(args)...) {}
 
-  /*! Disable copy constructor.
-   */
+  /*! Disable copy constructor. */
   Arr_counting_traits_2(const Arr_counting_traits_2&) = delete;
 
   /// @}
@@ -79,7 +78,7 @@ public:
   /*! Obtain the counter of the given operation */
   std::size_t count(Operation_id id) const;
 
-  /*! Print the compare_x counter */
+  /*! Print the counter associated with an operation. */
   template <typename OutStream>
   OutStream& print(OutStream& os, Operation_id id) const;
 
diff --git a/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/CGAL/Arr_tracing_traits_2.h b/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/CGAL/Arr_tracing_traits_2.h
index bf8f2e983a3..196003aa510 100644
--- a/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/CGAL/Arr_tracing_traits_2.h
+++ b/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/CGAL/Arr_tracing_traits_2.h
@@ -13,12 +13,12 @@ namespace CGAL {
 
 /*! \ingroup PkgArrangementOnSurface2TraitsClasses
  *
- * A meradata traits-class decorator for the arrangement package. It traces the
+ * A metadata traits-class decorator for the arrangement package. It traces the
  * invocations of traits-class functors. It is parameterized with another traits
  * class and inherits from it. For each traits method it prints out its input
  * parameters and its output result
  *
- * It models all the concept that the original trais models.
+ * It models all the concepts that the original traits models.
  */
 template <typename BaseTraits>
 class Arr_tracing_traits_2 : public BaseTraits {
@@ -61,8 +61,7 @@ public:
   template<typename ... Args>
   Arr_tracing_traits_2(Args ... args) : Base(std::forward<Args>(args)...) {}
 
-  /*! Disable copy constructor.
-   */
+  /*! Disable copy constructor. */
   Arr_tracing_traits_2(const Arr_tracing_traits_2&) = delete;
 
   /// @}
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_counting_traits_2.h b/Arrangement_on_surface_2/include/CGAL/Arr_counting_traits_2.h
index 45900997550..5829e4e7ea5 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_counting_traits_2.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_counting_traits_2.h
@@ -33,12 +33,12 @@
 namespace CGAL {
 
 /*! \class
- * A meradata traits-class decorator for the arrangement package. It counts the
+ * A metadata traits-class decorator for the arrangement package. It counts the
  * number of invocations of traits-class functors. It is parameterized with
  * another traits class and inherits from it. For each traits method it
  * maintains a counter that counts the number of invocations into the method.
  *
- * It models all the concept that the original trais models.
+ * It models all the concepts that the original traits models.
  */
 template <typename BaseTraits>
 class Arr_counting_traits_2 : public BaseTraits {
@@ -93,14 +93,13 @@ public:
     increment();
   }
 
-  /*! Disable copy constructor.
-   */
+  /*! Disable copy constructor. */
   Arr_counting_traits_2(const Arr_counting_traits_2&) = delete;
 
   /*! Obtain the counter of the given operation */
   std::size_t count(Operation_id id) const { return m_counters[id]; }
 
-  /*! Print the compare_x counter */
+  /*! Print the counter associated with an operation. */
   template <typename OutStream>
   OutStream& print(OutStream& os, Operation_id id) const {
     if (! m_exist[id]) return os;
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_tracing_traits_2.h b/Arrangement_on_surface_2/include/CGAL/Arr_tracing_traits_2.h
index 0404654079e..ae5370ed1a9 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_tracing_traits_2.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_tracing_traits_2.h
@@ -30,12 +30,12 @@
 namespace CGAL {
 
 /*! \class
- * A meradata traits-class decorator for the arrangement package. It traces the
+ * A metadata traits-class decorator for the arrangement package. It traces the
  * invocations of traits-class functors. It is parameterized with another traits
  * class and inherits from it. For each traits method it prints out its input
  * parameters and its output result
  *
- * It models all the concept that the original trais models.
+ * It models all the concepts that the original traits models.
  */
 template <typename BaseTraits>
 class Arr_tracing_traits_2 : public BaseTraits {
@@ -170,8 +170,7 @@ public:
   Arr_tracing_traits_2(Args ... args) : Base(std::forward<Args>(args)...)
   { enable_all_traces(); }
 
-  /*! Disable copy constructor.
-   */
+  /*! Disable copy constructor. */
   Arr_tracing_traits_2(const Arr_tracing_traits_2&) = delete;
 
   /*! Enable the trace of a traits operation