To add a new category to a page you can click the Category button at the bottom of the page and type in the name you'd like your category to be called.
A full list of existing categories can be found at Special:Categories.
Pages in category "Browse"
“ This is the page where you can request rollback, chat mod, moderator, admin, or bureaucrat...
“ This page is for promotion requests currently marked as completed. For new requests, please see...