Depends on your accomodation-I left an answer in your other question, but I can give a different one here.
In self-catered rooms, the contract is continous for however long-usually 40, 44 or 48 weeks. You have that room, uninterrupted, for that whole time, so can keep your stuff over the holidays or whatever. Most ( i think all) catered halls kick you out completely during the Easter break, because they rent these rooms out during this time. I also had a lot of people in catered complain about the fact that the times they served food were stupid-no lie ins if you want breakfast, and sometimes you had to miss evening meals if you wanted to attend lectures.
For my room they only provided a mattress-you need pillows, duvet, bedsheets and the rest. I'd bring coathangers as I cant remember if they had any of them either. If you have any more specific questions let me know.