Z4 (computer)

The Z4 was arguably the world's first commercial digital computer, and is the oldest surviving programmable computer. It was designed, and manufactured by early computer scientist Konrad Zuse's company Zuse Apparatebau, for an order placed by Henschel & Son, in 1942; though only partially assembled in Berlin, then completed in Göttingen in the Third Reich in April 1945, but not delivered before the collapse of Nazi Germany, in 1945. The Z4 was Zuse's final target for the Z3 design. Like the earlier Z2, it comprised a combination of mechanical memory and electromechanical logic.

The Z4 was used at the ETH Zurich from 1950 to 1955, also serving as the inspiration for the construction of the ERMETH, the first Swiss computer, created under the direction of ETH engineer Ambros Speiser.