The official documentation is at: http://docs.alfresco.com
The component library page contains sections for each JSF component created for the web-client.
Each entry should show a basic tag description, example component usage and screenshots of the component in action if applicable.
The following are plain JSF components and independent of the Alfresco Repository. They could be repackaged and used outside the Alfresco web-client:
The following components provide functionality specific to the Alfresco Repository:
The following component(s) were found when exploring Alfresco Web client (declared in 'repo.tld'):