The Hut 6 Story: How Gordon Welchman and Alan Turing solved the puzzle of the Enigma Machine and helped win World War II
Near the end of World War I, German engineer Arthur Scherbius invented a cipher device, patented it and around 1920 began marketing it, calling it the Enigma machine.
Eventually, the machine was adopted by the military and government services of Nazi Germany before World War II. German military planning emphasized agile tactics (such as the blitzkrieg) which depended heavily on radio communication to achieve coordination. Since it was probable that the radio signals would be intercepted, messages had to be encoded to be secure. Compact and lightweight, the Enigma machine was the perfect solution for this problem. The German Navy, Army and Air Force added to the machine a plugboard, making its encryption capacity even more complex and began using it for their daily communications.
The Enigma had a rotor mechanism that would scramble the 26 letters of the alphabet. An operator would enter text on the machine’s keyboard and another person would note which letter would light up with each key press. When plain text would be entered, the illuminated letters would be the encrypted text. Entering the encrypted text would transform it back to plain text.
