This book explains the workings and applications of the operational amplifier, one of the most popular and versatile building-blocks used in modern electronic circuit design. The ten chapters cover the operating principles and the special types of op-amp, and there are some 300 practical circuits, diagrams and tables. The book is intended for the practical design engineer, technician and experimenter, but should also interest the electronics student and the amateur. The language used throughout is easy-to-understand and non-mathematical.