Cambridge's unique teaching system. The focus is on you getting the most out of your course, looking more closely at issues raised by lecturers and going over work to sort out any problems. It's a chance for you to have your questions answered in a 1-/2-/3-to-1 basis. The number of supervisions you'll have and the amount and type of work will vary with subject and term, but they're compulsory. They are the academic focal-point of your time here so it's in your interests to make the most of them. If you're not quite surehow to use supervisions to your best advantage (after getting used to the system a bit first), get in touch with your DoS, Tutor, or, of course, your Subject reps.