Why use SSH?

One of the most important reasons that you should use SSH is that you will have to on many of the machines: cubane and the ncsa accounts accept only ssh and silicon will accept only ssh from out-of-department IP addresses (Bruin Online or other ISP you may be using
The other reason is that it can dramatically reduce the risk of having a security incident that wipes out a week of one of your coworker's time and possibly your data (since the last backup)
While ssh is not required on all of the computers yet, it may be in the near future on many other accounts because it is so much safer

More info on ssh and ssh client programs