Book excerpt: Mechanical comprehension tests are used widely during technical selection tests within the careers sector. Mechanical comprehension and reasoning tests combine many different elements. The test itself is usually formed of various pictures and diagrams that illustrate different mechanical concepts and principles. Mechanical comprehension and reasoning tests are normally highly predictive of performance in manufacturing, technical and production jobs. This comprehensive guide will provide you with sample test questions and answers to help you prepare for your mechanical comprehension test. An explanation of the tests and what they involve; Sample timed-tests to assist you during your preparation; Advice on how to tackle the tests; Understanding mechanical advantage; Answers and explanations to the questions; An introduction chapter for fault diagnosis.