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FORT HUACHUCA, Ariz. -- When Ralph Van Deman established the War Department's intelligence organization shortly after the United States entered World War I, he was faced with the daunting task of ...

In March 1809, Europe was perched on the precipice of war as Napoleon's forces braced for an attack from Austria. Intent on identifying enemy troop positions to his top commanders, Napoleon sent a ...

Block ciphers are invertible symmetric key cryptographic algorithms. Here, symmetric means that the same cryptographic key is used to both encrypt and decrypt messages. The key is used to transform ...

Edward Hebern of California designed this machine to encipher and decipher typed messages. It uses one of the most important developments in cipher machines, the rotor. Rotary cipher machines were ...

You could do worse than to confuse the meanings of "code" and "cipher"—even cryptographers sometime use the terms as though they had the same meaning. There is, however, a definite distinction between ...

Sam Blake, an Australian mathematician, first learned of the Zodiac Killer’s unsolved ciphers — a series of encrypted messages — from a documentary in the 1990s. His interest marginally increased in ...