Enbedding Script Resources

the difference between retrieved from the filesystem compared with embedded as a resource in a dll:
When the page to a script is used, the ScriptManager provides a callback to the ScriptRecource handler, which retrieves the contents.When retrieved as an embedded resource, the ScriptManager injects the call to Sys.Application.notifyScriptLoaded for you automatically. This allows you to start using scripts that you already have with ASP.NET AJAX without having to rebuild the dlls.