Two Manchester Computer Milestones

Abstract

On June 21, 2022 in Manchester, England, the IEEE unveiled two bronze Milestone plaques in recognition of two historic computing developments. The first honored the Manchester University Baby computer and its derivatives, 1948–1951. The second plaque marked the Atlas computer and the invention of virtual memory, 1957– 1962. Both projects benefitted from a significant long-term collaboration between the University and industry (Ferranti Ltd.). The formal citations are as follows: At this site, on June 21 1948, the “Baby” became the first computer to execute a program stored in addressable read-write electronic memory. “Baby” validated Williams-Kilburn Tube random-access memories, later widely used, and led to the 1949 Manchester Mark I which pioneered index registers. In February 1951, Ferranti Ltd.’s commercial derivative became the first electronic computer marketed as a standard product delivered to a customer. The Atlas computer was designed and built in this building by Tom Kilburn and a joint team of the University of Manchester and Ferranti Ltd. The most significant new feature of Atlas was the invention of virtual memory, allowing memories of different speeds and capacities to act as a single large fast memory separately available to multiple users. Virtual memory became a standard feature of general-purpose computers.