Manchester Small-Scale Experimental Machine

The Small-Scale Experimental Machine was the first based on the Von Neumann architecture computer, built with tubes.

It was developed to investigate from 1945 at the Victoria University of Manchester by Frederic Calland Williams, Tom Kilburn and Geoff Tootill to phenomena of the Williams tube. This was used as a memory after a process developed Williams 1946 to reclaim memory within milliseconds. In June 1948, so it was verified that both program memory in the computer memory work can be kept.

This is the prototype of the later developed Manchester Mark I.