The exam consists of around 50 multiple-choice questions (with 3..4 possible answers for each question). The exam is open book (you can bring on the course's book to consult if necessary). No other notes can be however brought except the book.
An example exam is available here. This includes questions, answers, and the discussion of the right and wrong answers, with references to the relevant book chapters.
Other important points
Each exam question counts equally towards the exam grade.
Although the exam is open-book, please note that there are quite many questions you have to solve in the allowed time. As such, there is definitely not enough time to consult the book for every question you have to answer.
Read the questions carefully while answering them. A good strategy is to eliminate the obviously incorrect answers first, and work out the right answer incrementally from the remaining set.