Programmable electronic computer now 62 years old

On 31 January 1944 the first programmable electronic computer in the world, the Colossus Mark I, was installed in the British cryptographers' headquarters in Bletchley Park.

It had been constructed over the previous ten months by Tommy Flowers, at the British Post Office Research Station at Dollis Hill in North London, for the purpose of breaking German cypher codes.

Colossus predated its more famous cousin ENIAC by two years. The machine operated on 1,500 vacuum tubes (ENIAC would use around 18,000) and was programmed by paper tape which was optically read. Because of the fragility of the vacuum tubes, the machines, once turned on, were never powered down until the World War's end.

The machine helped the Allied Forces win the war, and in honour of that a replica was built in 2003, which can still be admired at the Bletchley Park Museum.