I am new to this alfresco, I want to customize the complete UI (Header, Content & Footer) page of the alfresco as per my requirement. First of all I want to know that, is it possible to do? If yes then how can I do this.
The Share UI is built on the Surf framework. Surf is built on web scripts. Everything you see in the UI is the result of the output of a web script that is running in the Share tier. Those web scripts may or may not be making remote calls back to the repository tier to retrieve data.
If you want to change the Share UI, it is usually a matter of overriding Share-tier web scripts. In Alfresco 4, there are new extension points for changing the UI.