Small-Scale Experimental Machine

The Manchester Small-Scale Experimental Machine (SSEM), nicknamed Baby, was the first stored-program computer to run a program, on June 21, 1948. It was developed by Frederic C. Williams and Tom Kilburn at the University of Manchester.

The SSEM developed into the Manchester Mark I which led to the Ferranti Mark I, the world's first commercially available general-purpose computer.

At around the same time EDSAC was being developed at the University of Cambridge Mathematical Laboratory.