Mention external modules.
diff --git a/include/freetype/ftmodapi.h b/include/freetype/ftmodapi.h
index 3f7ae82..f4246dc 100644
--- a/include/freetype/ftmodapi.h
+++ b/include/freetype/ftmodapi.h
@@ -45,10 +45,12 @@
*
* @description:
* The definitions below are used to manage modules within FreeType.
- * Modules can be added, upgraded, and removed at runtime. Additionally,
- * some module properties can be controlled also.
+ * Internal and external modules can be added, upgraded, and removed at
+ * runtime. For example, an alternative renderer or proprietary font
+ * driver can be registered and prioritized. Additionally, some module
+ * properties can also be controlled.
*
- * Here is a list of possible values of the `module_name` field in the
+ * Here is a list of existing values of the `module_name` field in the
* @FT_Module_Class structure.
*
* ```
