diff --git a/course/lib.php b/course/lib.php
index 0c1d2deb6c7..06f84568064 100644
--- a/course/lib.php
+++ b/course/lib.php
@@ -556,11 +556,11 @@ function get_array_of_activities($courseid) {
 }
 
 /**
- * Returns the localised human-readable names of all used modules
+ * Returns an array where the key is the module name (component name without 'mod_')
+ * and the value is a lang_string object with a human-readable string.
  *
- * @param bool $plural if true returns the plural forms of the names
- * @return array where key is the module name (component name without 'mod_') and
- *     the value is the human-readable string. Array sorted alphabetically by value
+ * @param bool $plural If true, the function returns the plural forms of the names.
+ * @return lang_string[] Localised human-readable names of all used modules.
  */
 function get_module_types_names($plural = false) {
     static $modnames = null;
diff --git a/lib/modinfolib.php b/lib/modinfolib.php
index 8b8f44ca623..84ccd14ed73 100644
--- a/lib/modinfolib.php
+++ b/lib/modinfolib.php
@@ -1500,10 +1500,10 @@ class cm_info implements IteratorAggregate {
     }
 
     /**
-     * Returns a localised human-readable name of the module type
+     * Returns a localised human-readable name of the module type.
      *
-     * @param bool $plural return plural form
-     * @return string
+     * @param bool $plural If true, the function returns the plural form of the name.
+     * @return lang_string
      */
     public function get_module_type_name($plural = false) {
         $modnames = get_module_types_names($plural);