Provides support to all components that render. This is primarily about generating unique client-side ids (very important for JavaScript generation) as well as accumulating JavaScript to be sent to the client. PageRenderSupport also allows for the incremental addition of stylesheets.
When rendering, a <script> block will be added to the bottom of the page (just before the </body> tag). The scripting statements added to this block will be executed, on the client, only once the page has fully loaded.