Business week is running a series of articles on some of the greatest inventors of the past 75 years. Their latest is a piece on Alan Turing, a British mathematician who conceived of and helped invent the first programmable "universal machine". Turing's ideas and skills were put to use breaking German codes throughout World War II.
To be fair, Alan Turing did not wholly invent the concept of a programmable machine. That honor goes to Charles Babbage, who conceived of an "Analytical Engine". The Analytical Engine was programmed with punch cards, or it would have been if it had ever been made. Though some of Babbage's conceptual designs, like the "Difference Engine", were later completed, the Analytical Engine never made it out of the drawing room.
Babbage was also one of the first to use mathematics to break a code. In fact, he applied his ideas towards breaking a Viginere autokey cipher. For 200 years, most people had thought the autokey code unbreakable. A century later, the people at the Government Code and Cypher School -- in a Victorian mansion named Bletchley Park -- would apply Alan Turing's theories of mathematics to crack another "unbreakable" code.
The COLOSSUS, the first digital, programmable electronic computer, was used to break German Fish teletype cyphers. Instead of a punch card system, COLOSSUS read instructions from a tape. Instead of silicon and transistors, COLOSSUS was a collection of servomotors and metal. However, despite it's revolutionary nature, COLOSSUS was of no use against the more advanced German Enigma code.
A Polish scientist, Marian Rejewski, had broken pre-war Enigma codes using a machine called a Bomba. The Bomba emulated the Enigma machine and used brute force to attack the code. Alan Turing redesigned the Bomba, applying his mathematical theories to the making of "Bombes". Turing had exploited a weakness, not in the Enigma code, but in the way Enigma machine was used.
Bombes were able to break many Enigma based ciphers in hours. It is argued that Turing's work ended the war years earlier than would have been possible otherwise. Turing would later go on to invent some of the earliest, electronic, programmable computers at the National Physical Laboratory and the University of Manchester.