There is a command, "finger" which looks up user information within the  
system. (It's supposed to imply running your finger down a list, not what
you think :)

<ASIDE>
It used to be commonly used to find info about users on other networks,
but that has been disabled due to abuse (spammers would run

 finger @cs.toronto.edu

to build lists of addresses to spam.)
</ASIDE>

Nevertheless it is still often used at DCS internally to look up other
users. To find out what information you have listed about yourself run the
command "finger YourUserName@cs.toronto.edu"  (replace YourUserName with
your username ). If the info returned is not current, fix it with the
chfn command. Log into a cslab machine ( a "cslab prompt" ) and type

 chfn

Follow the prompts to update the information.