Colossus was the first computer in the world to be fully electronic, digital and programmable. The machine was designed in the early 1940s by Tommy Flowers and put into operation in 1943. The device was a special computer focused on Nazi encryption. Colossus did not crack the codes directly, but processed encrypted messages, simulated mechanical code breakers, and then generated potential key combinations that could decrypt encrypted communications.
By today's standards it was quite limited as programmable machines go. It was not possible to store programs in the machine, so each new program had to be entered manually with a series of switches and plugs. In addition, the war after the war was of limited use, as it was specifically designed for cryptographic tasks and could not easily be adapted for civilian needs ̵
After the program ended, the machines (nearly a dozen Mark 1 and Mark 2 brand computers), documentation and plans were destroyed in the 1960s to ensure the project's secrecy and decades of staffing. The project was never recognized for its achievements , In the 2000s, a project to reconstruct a Colossus Mark 2 began with input and guidance from the remaining engineers working on the original computers. The project was completed in 2008 and the rebuilt Colossus participated in a Cipher Challenge – a competition to see which code breakers around the world were able to decrypt original encrypted World War II messages the fastest. The machine did not win (it lost to a modern computer), but it was discovered that the easy-to-use Colossus was about the equivalent of a 5.8-MHz chip – an extremely impressive representation of a computer running in The computer was installed in the early 1940s.
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