Z5 (computer)

The Z5 was a computer designed by Konrad Zuse and manufactured by Zuse KG following an order by Ernst Leitz GmbH in Wetzlar in 1950.

The computer was delivered in July 1953[1] and was the first commercial built-to-order mainframe in Germany.

The computer was purchased to help with the design of optical lens systems.

Zuse implemented the machine with relays, since vacuum tubes were too unreliable at the time.

It had conditional branching and five subroutine loops.