Shannon, who would later work with William Friedman and other cryptologists on secret NSA projects, also enjoyed thinking about codes and ciphers. While employed at Bell Labs, he came up with the insight that the problem of communicating through a noisy system, like a phone wire, is almost identical to the process of enciphering and deciphering a message. In other words, according to Shannon, making yourself understood to another person is essentially a problem of cryptology. You reduce the noise of the channel between you (instead of noise, Shannon called it “information entropy”) in a way
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