There are two main public transportation systems that can be used. Unfortunately, they can hardly be called the most efficient! Most people in Southern California do have cars because the distances are so large. Many freshman live most of their first year quite happily without a car because everything you really need is available and there are 25 restaurants within a one mile radius.
However, all of this does not mean that you won't be able to venture off of campus once in awhile and get to know the beaches and museums of the Los Angeles area.
Check out the following two links. Once you know where you want to go, simply type it into the trip planner and it will chart your course, how long it will take, and how much it will cost.
http://www.metro.net
http://www.octa.net