Gallery of Early Computers (1940s – 1960s)

Designed by the legendary German engineer Konrad Zuse, the Z4 was a follow-up to its pioneering predecessor, the Z3 computer he built in 1941 (the world’s first programmable, automatic computing machine). The first version had 512 bytes of main memory and could do 20,000 instructions per second, although a switch to a different kind of memory later doubled its performance and made it the fastest computer of its time. The IBM Naval Ordnance Research Calculator was arguably the first supercomputer and was the most powerful computer of its time.

Source: royal.pingdom.com