tagging

Hi. im new to xwiki. a great software! i have trouble locating the documentation on how to use and create tags (tag cloud) in xwiki. what is the syntax? how do i creat tags? is there a gui for creating them? thaks very much, sorry if this has been answerd before, i couldn't find any data about it by using the search on the xwiki site and on this users list. Yuda.