Abstract
Traffic management barely existed in 1959 when this publication was launched. There were traffic signals but since the 1960s, when traffic engineering emerged as a discipline, the growth of traffic management has been in parallel with the development of computers, and the acceleration in data transmission. This article discusses the various signal design techniques developed around this time, such as point controllers moving from electro-mechanical to solid-state controllers, and the advent of the microprocessor, which enabled a standard set of hardware to be programmed to provide a huge range of features by just changing how the controller software performed.