The main purpose of this book is to demystify automatic test equipment. Existing literature on automatic test equipment is often written by engineers who look at automatic test equipment from inside-out. However, engineers are not renowned for high qualities of authorship. Other main sources of literature are worldwide standards. But these do not usually explain automatic test equipment; instead they merely formalize its component parts. From any existing literature therefore it is difficult to ask the question,"What is automatic test equipment"? and find a satisfactory answer. This book is for anyone who has an interest in automatic test equipment - anyone in the industry who needs to know what types of equipment are available, what each type is capable of doing, what tests are performed, what computer buses are used, what the buses are capable of, and so on, will find answers here. Managers, engineers, technicians, scientists, students, teaches, graduates, those in purchasing positions should benefit. It is a general-purpose book, which explains concepts, and also a reference book which defines specifications.