This text describes in practical terms how to use a desk-top computer to monitor and control laboratory experiments. The author clearly explains how to design electronic circuits and write computer programs to sense, analyse and display real-world quantities, including displacement, temperature, force, sound, light, and biomedical potentials. The book includes numerous laboratory exercises and appendices that provide practical information on microcomputer architecture and interfacing, including complete circuit diagrams and component lists. Topics include analog amplification and signal processing, digital-to-analog and analog-to-digital conversion, electronic sensors and actuators, digital and analog interfacing circuits, and programming. Only a very basic knowledge of electronics is assumed, making it ideal for college-level laboratory courses and for practising engineers and scientists.