Sinclair ZX80 microcomputer, 1980.

The Sinclair ZX80 was the first computer made to appeal to the mass market. Sinclair Research Ltd of Cambridge developed it as a build-it-yourself programmable computer that was designed to connect to a television set or cassette recorder. It was small and lightweight, weighing just 12 ounces and was accessible to a much wider sector of the population, being priced at just £99. All these characteristics made the Sinclair ZX80 the forerunner of a whole generation of personal computers.