The theory test is made up of a multiple-choice part and a hazard perception part. You need to pass both parts to pass the theory test.

Part 1 - Multiple Choice

Part 2 - Hazard Perception

14 video clips will be shown to the candidate of various road scenes. Within each clip there will be at least one developing hazard. One of the clips will contain two. The sooner the candidate responds to the hazard, the higher the score. The maximum score for each clip is 5. The pass mark is 44 or more out of a possible 75 marks.
From Monday 28th September 2009 the Driving Standards Agency (DSE) has introduced case studies into the driving theory test. One case study will now be included in the exam for car drivers.
As part of the multiple choice section of the test, the case study assesses candidate's understanding of driving theory, while the multiple choice questions continue to assess their knowledge of the subject. The theory test case study takes the form of a scenario, or short story, on which five questions will be based. Candidates answer the questions in the same way as they complete the rest of the test, using either a touch screen or a mouse. The pass rate remains the same 44/75 or 59%.

Before the test starts you'll be given instructions on how the test works.
You can also choose to go through a practice session of the multiple choice questions to get used to the layout of the test. At the end of the practice session the real test will begin.
A question and several answer options will appear onscreen and you have to select the correct answer to the question by touching the screen. Some questions may require more than one answer.
For cars and motorcycles you'll be asked 50 questions in 57 minutes and the pass mark is 43 out of 50.
You can navigate between questions and 'flag' questions that you want to come back to later in the test. After the multiple choice part you can choose to have a break of up to three minutes before the hazard perception part starts.