diff --git a/core/includes/ajax.inc b/core/includes/ajax.inc
index 0b897b8..3f2389f 100644
--- a/core/includes/ajax.inc
+++ b/core/includes/ajax.inc
@@ -204,9 +204,9 @@
  *   $commands[] = ajax_command_replace('#object-1', 'some html here');
  *   // Add a visual "changed" marker to the '#object-1' element.
  *   $commands[] = ajax_command_changed('#object-1');
- *   // Menu 'page callback' and #ajax['callback'] functions are supposed to
- *   // return render arrays. If returning an Ajax commands array, it must be
- *   // encapsulated in a render array structure.
+ *   // #ajax['callback'] functions are supposed to return render arrays. If
+ *   // returning an Ajax commands array, it must be encapsulated in a render
+ *   // array structure.
  *   return array('#type' => 'ajax', '#commands' => $commands);
  * @endcode
  *
diff --git a/core/modules/system/system.api.php b/core/modules/system/system.api.php
index 600b06b..abda14e 100644
--- a/core/modules/system/system.api.php
+++ b/core/modules/system/system.api.php
@@ -504,145 +504,6 @@ function hook_menu_get_item_alter(&$router_item, $path, $original_map) {
  * paths and whose values are an associative array of properties for each
  * path. (The complete list of properties is in the return value section below.)
  *
- * @section sec_callback_funcs Callback Functions
- * The definition for each path may include a page callback function, which is
- * invoked when the registered path is requested. If there is no other
- * registered path that fits the requested path better, any further path
- * components are passed to the callback function. For example, your module
- * could register path 'abc/def':
- * @code
- *   function mymodule_menu() {
- *     $items['abc/def'] = array(
- *       'page callback' => 'mymodule_abc_view',
- *     );
- *     return $items;
- *   }
- *
- *   function mymodule_abc_view($ghi = 0, $jkl = '') {
- *     // ...
- *   }
- * @endcode
- * When path 'abc/def' is requested, no further path components are in the
- * request, and no additional arguments are passed to the callback function (so
- * $ghi and $jkl would take the default values as defined in the function
- * signature). When 'abc/def/123/foo' is requested, $ghi will be '123' and
- * $jkl will be 'foo'. Note that this automatic passing of optional path
- * arguments applies only to page and theme callback functions.
- *
- * @subsection sub_callback_arguments Callback Arguments
- * In addition to optional path arguments, the page callback and other callback
- * functions may specify argument lists as arrays. These argument lists may
- * contain both fixed/hard-coded argument values and integers that correspond
- * to path components. When integers are used and the callback function is
- * called, the corresponding path components will be substituted for the
- * integers. That is, the integer 0 in an argument list will be replaced with
- * the first path component, integer 1 with the second, and so on (path
- * components are numbered starting from zero). To pass an integer without it
- * being replaced with its respective path component, use the string value of
- * the integer (e.g., '1') as the argument value. This substitution feature
- * allows you to re-use a callback function for several different paths. For
- * example:
- * @code
- *   function mymodule_menu() {
- *     $items['abc/def'] = array(
- *       'page callback' => 'mymodule_abc_view',
- *       'page arguments' => array(1, 'foo'),
- *     );
- *     return $items;
- *   }
- * @endcode
- * When path 'abc/def' is requested, the page callback function will get 'def'
- * as the first argument and (always) 'foo' as the second argument.
- *
- * If a page callback function uses an argument list array, and its path is
- * requested with optional path arguments, then the list array's arguments are
- * passed to the callback function first, followed by the optional path
- * arguments. Using the above example, when path 'abc/def/bar/baz' is requested,
- * mymodule_abc_view() will be called with 'def', 'foo', 'bar' and 'baz' as
- * arguments, in that order.
- *
- * Special care should be taken for the page callback drupal_get_form(), because
- * your specific form callback function will always receive $form and
- * &$form_state as the first function arguments:
- * @code
- *   function mymodule_abc_form($form, &$form_state) {
- *     // ...
- *     return $form;
- *   }
- * @endcode
- * See @link form_api Form API documentation @endlink for details.
- *
- * @section sec_path_wildcards Wildcards in Paths
- * @subsection sub_simple_wildcards Simple Wildcards
- * Wildcards within paths also work with integer substitution. For example,
- * your module could register path 'my-module/%/edit':
- * @code
- *   $items['my-module/%/edit'] = array(
- *     'page callback' => 'mymodule_abc_edit',
- *     'page arguments' => array(1),
- *   );
- * @endcode
- * When path 'my-module/foo/edit' is requested, integer 1 will be replaced
- * with 'foo' and passed to the callback function. Note that wildcards may not
- * be used as the first component.
- *
- * @subsection sub_autoload_wildcards Auto-Loader Wildcards
- * Registered paths may also contain special "auto-loader" wildcard components
- * in the form of '%mymodule_abc', where the '%' part means that this path
- * component is a wildcard, and the 'mymodule_abc' part defines the prefix for a
- * load function, which here would be named mymodule_abc_load(). When a matching
- * path is requested, your load function will receive as its first argument the
- * path component in the position of the wildcard; load functions may also be
- * passed additional arguments (see "load arguments" in the return value
- * section below). For example, your module could register path
- * 'my-module/%mymodule_abc/edit':
- * @code
- *   $items['my-module/%mymodule_abc/edit'] = array(
- *     'page callback' => 'mymodule_abc_edit',
- *     'page arguments' => array(1),
- *   );
- * @endcode
- * When path 'my-module/123/edit' is requested, your load function
- * mymodule_abc_load() will be invoked with the argument '123', and should
- * load and return an "abc" object with internal id 123:
- * @code
- *   function mymodule_abc_load($abc_id) {
- *     return db_query("SELECT * FROM {mymodule_abc} WHERE abc_id = :abc_id", array(':abc_id' => $abc_id))->fetchObject();
- *   }
- * @endcode
- * This 'abc' object will then be passed into the callback functions defined
- * for the menu item, such as the page callback function mymodule_abc_edit()
- * to replace the integer 1 in the argument array. Note that a load function
- * should return NULL when it is unable to provide a loadable object. For
- * example, the node_load() function for the 'node/%node/edit' menu item will
- * return NULL for the path 'node/999/edit' if a node with a node ID of 999
- * does not exist. The menu routing system will return a 404 error in this case.
- *
- * @subsection sub_argument_wildcards Argument Wildcards
- * You can also define a %wildcard_to_arg() function (for the example menu
- * entry above this would be 'mymodule_abc_to_arg()'). The _to_arg() function
- * is invoked to retrieve a value that is used in the path in place of the
- * wildcard. A good example is user.module, which defines
- * user_uid_optional_to_arg() (corresponding to the menu entry
- * 'tracker/%user_uid_optional'). This function returns the user ID of the
- * current user.
- *
- * The _to_arg() function will get called with three arguments:
- * - $arg: A string representing whatever argument may have been supplied by
- *   the caller (this is particularly useful if you want the _to_arg()
- *   function only supply a (default) value if no other value is specified,
- *   as in the case of user_uid_optional_to_arg().
- * - $map: An array of all path fragments (e.g. array('node','123','edit') for
- *   'node/123/edit').
- * - $index: An integer indicating which element of $map corresponds to $arg.
- *
- * _load() and _to_arg() functions may seem similar at first glance, but they
- * have different purposes and are called at different times. _load()
- * functions are called when the menu system is collecting arguments to pass
- * to the callback functions defined for the menu item. _to_arg() functions
- * are called when the menu system is generating links to related paths, such
- * as the tabs for a set of MENU_LOCAL_TASK items.
- *
  * @section sec_render_tabs Rendering Menu Items As Tabs
  * You can also make groups of menu items to be rendered (by default) as tabs
  * on a page. To do that, first create one menu item of type MENU_NORMAL_ITEM,