A broad introduction to what expert systems are and what they do which reveals the principles underlying their operation. It looks at how knowledge is obtained and considers how it can then be made available to the computer. System design and creation is also described. The books in this series are aimed at college students whose courses include IT components, including BTEC National and Higher Level courses, RSA and City & Guilds courses, as well as courses designed for professional bodies. The books adopt active learning strategies. Each chapter begins with a statement of what learning objectives the student is expected to achieve and at key points in a chapter the student is given the opportunity to achieve them by carrying out short tasks and by undertaking the assignment at the end of the chapter. Feedback on tasks is provided at the end of a chapter.