Inserts some info about on the currently logged in member. On member detail pages, extra options are available to show the same information for the requested member.
When the visitor is not logged in, the your... parameters will insert nothing
Information on the logged in member:
Information on the requested member (only available on member detail pages):
all
<%if(loggedin)%>
you are <%member(yourrealname)%>
<%endif%>