Academic Advisor
From GradBook
Ripped off from the CSAIL info for new students:
Your academic advisor is the person who keeps track of your progress through the PhD program. You generally meet with him or her once a term when you register for classes (known as "reg day"). He or she can answer questions you have about progress through your program; however, for the most part you will not see very much of your academic advisor. Your research advisor is likely the person you will work most closely with during your time here, so it is important that you find a good match and that you feel comfortable talking to your research advisor.
Your academic advisor is also the first resource to talk to if you're having trouble with EECS requirements or with your research advisor. Your research advisor may be an excellent resource for academic advice too, and it's a good idea to discuss your plans for classes, especially your class projects, with your research advisor.