diff --git a/reference/yaf/yaf-loader.xml b/reference/yaf/yaf-loader.xml
index 4113c8a761..ea897956a8 100644
--- a/reference/yaf/yaf-loader.xml
+++ b/reference/yaf/yaf-loader.xml
@@ -12,8 +12,71 @@
   <section xml:id="yaf-loader.intro">
    &reftitle.intro;
    <para>
-
+    <classname>Yaf_Loader</classname> introduces a comprehensive autoloading
+    solution for Yaf.
    </para>
+   <para>
+    The first time an instance of <classname>Yaf_Application</classname> is retrieved, 
+    <classname>Yaf_Loader</classname> will instance a singleton, and registers itself with
+    spl_autoload.  You retrieve an instance using the <methodname>Yaf_Loader::getInstance</methodname>
+   </para>
+
+   <para>
+    By default, <classname>Yaf_Loader</classname> assume all Class will store
+    in the <link linkend="yaf.configuration">global class
+     directory</link>, which is defined in the php.ini(yaf.library).
+   </para>
+
+   <para>
+    If you want <classname>Yaf_Loader</classname> search some Class in the
+    <link linkend="yaf-loader.props.library">local class
+     directory</link>(which is defined in application.ini, and by default,
+    it is APPLICATION_PATH . "/libraray"), you should register the class prefix using the
+    <methodname>Yaf_Loader::registerLocalNameSpace</methodname>
+   </para>
+
+   <para>
+   <programlisting role="php">
+<![CDATA[
+// Assuming the following configure in php.ini:
+yaf.libraray = "/global_dir"
+
+//Assuming the following configure in application.ini
+application.libraray = APPLICATION_PATH "/library"
+
+//Assuming the following local name space registerd:
+<?php
+class Bootstrap extends Yaf_Bootstrap_Abstract{
+      public function _initLoader($dispatcher) {
+           Yaf_Loader::getInstance()->registerLocalNameSpace(array("Foo", "Bar"));
+      }
+?>
+]]>
+   </programlisting>
+
+   then the autoload examples:
+   <programlisting role="bash">
+<![CDATA[
+class Foo_Bar_Test =>
+  // APPLICATION_PATH/library/Foo/Bar/Test.php
+  
+class GLO_Name  =>
+  // /global_dir/Glo/Name.php
+ 
+//as of PHP 5.3, you can use namespace
+class \Foo\Bar\Dummy =>
+   // APPLICATION_PATH/library/Foo/Bar/Dummy.php
+
+class \FooBar\Bar\Dummy =>
+   // /global_dir/FooBar/Bar/Dummy.php
+]]>
+   </programlisting>
+  </para>
+
+  <para>
+    You may noticed that all the folder is Ucfisted, you can make them all
+    lowcase by set yaf.lowcase_path = On in php.ini
+  </para>
   </section>
 <!-- }}} -->
 
@@ -71,7 +134,11 @@
     <varlistentry xml:id="yaf-loader.props.library">
      <term><varname>_library</varname></term>
      <listitem>
-      <para></para>
+      <para>
+      By default, this value is APPLICATION_PATH . "/library", you can change
+      this either in the application.ini(application.library) or call to
+      <methodname>Yaf_Loader::setLibraryPath</methodname>
+      </para>
      </listitem>
     </varlistentry>
     <varlistentry xml:id="yaf-loader.props.global-library">
@@ -92,6 +159,7 @@
 
 
  </partintro>
+ 
 
  &reference.yaf.entities.yaf-loader;