diff --git a/docs/sourcetree.html b/docs/sourcetree.html
index 41f40351eb7..00dc4e7c9f4 100644
--- a/docs/sourcetree.html
+++ b/docs/sourcetree.html
@@ -48,6 +48,7 @@ each directory.
 	<li><b>glslcompiler</b> - a stand-alone GLSL compiler driver
         <li>XXX more
         </ul>
+    <li><b>es</b> - OpenGL ES overlay, parallelly buildable with the core Mesa
     <li><b>math</b> - vertex array translation and transformation code
         (not used with Gallium)
     <li><b>ppc</b> - Assembly code/optimizations for PPC systems
@@ -123,15 +124,15 @@ each directory.
       </ul>
     <li><b>state_trackers</b> -
        <ul>
-       <li><b>dri</b> -
-       <li><b>egl</b> -
-       <li><b>es</b> -
+       <li><b>dri</b> - Meta state tracker for DRI drivers
+       <li><b>egl</b> - Meta state tracker for EGL drivers
+       <li><b>es</b> - OpenGL ES 1.x and 2.x state trackers
        <li><b>g3dvl</b> -
-       <li><b>glx</b> -
+       <li><b>glx</b> - Meta state tracker for GLX
        <li><b>python</b> -
-       <li><b>vega</b> -
+       <li><b>vega</b> - OpenVG 1.x state tracker
        <li><b>wgl</b> -
-       <li><b>xorg</b> -
+       <li><b>xorg</b> - Meta state tracker for Xorg video drivers
        </ul>
     <li><b>winsys</b> -
        <ul>