Altair 8800b Working System, made by Micro Instrumentation and Telemetry Systems (MITS), United States, 1977-1982.

The Altair was widely acknowledged as the first home computer kit. It was developed by Ed Roberts, an American electronics enthusiast who had founded a company called Model Instrumentation and Telemetry Systems (MITS), originally to sell calculator kits. He was able to source Intel 8080 microchips to power the computer kits for just $75, when the standard retail price was $350, meaning that the kit could be sold for less that $400. Roberts expected to sell a few hundred build-it-yourself kits to dedicated hobbyists, but thousands of kits were bought in the first month. The front switch Altair system was never sold in the UK - this computer was imported from the US by the Head of Technology at a Secondary school in Kent in the late 1970s.