The Next Generation

The transistor (G) characterized the second-generation computers. Transistors were made of a semiconducting material and controlled the flow of electricity through the circuits. They also allowed computers to become smaller and more powerful and faster at the same time. The transistor was invented in 1947, won the Nobel Prize in 1956 but was not used in computers until 1959. They were also less expensive, smaller, required less electricity, and emitted less heat than vacuum tubes.

Magnetic tape was still the most commonly used external storage medium, while magnetic disk storage was used so data could be located more rapidly. MIT developed magnetic core storage in which each core stored one bit ot information. Punched cards and magnetic tape were still used for inpu, while punched cards and paper constitued the output.

Programming languages became more sophisticated as high-level languages (such as FORTRAN, COBOL, BASIC, and PL/I) resembling English were developed. however, computers were still under the control of human operators.