Sometimes you may be invited for an interview before a decision is made. This could be the normal practice for that particular course, or it could be because your application is unusual in some way and the university wants to check that you are really suitable (perhaps you are a mature student without the usual formal qualifications).
If you find that you don't have a place then you will be eligible for the UCAS Clearing scheme, a way of matching universities without students to students without universities.
