This volume describes General Electric Corporation's venture into developing second and third generation mainframe computer systems.The General Electric Corporation (GE), which began its life as the Edison Electric Co., was long involved in electrical appliances and industrial machines. It was also a founder of the Radio Corporation of America, which eventually became one of its competitors, and developed many electrical systems in order to control different types of industrial machines. Its breakthrough into computing came with its winning bid to provide the computing systems for the Electronic Recording Method of Accounting) system developed for the Bank of America by the Stanford Research Institute. The success of this project led GE to develop the GE-200 series which was the foundation for commercial timesharing. The GE-235 was selected by Dartmouth for its Dartmouth Time Sharing System (DTSS), an innovative academic time-sharing system. BASIC was developed on the GE-235 computer system under DTSS. GE enhanced it to develop its Mark II/III Time Sharing System, apparently the first commercial time sharing service in the world. GE develop the GE-300/-400 systems for industrial process control. The GE-600 series replaced the GE-200 series and demonstrated innovation in time-sharing systems. The GE-645 was selected to host Multics, which was developed by MIT. However, GE felt that it could not compete in computing against IBM, Univac, and other mainframes competitors, so it folded its tent and sold its Computer Division to Honeywell, Inc. Nevertheless, GE will be remembered for many innovations which continue to be used in modern computing systems.