CODE VS. CIPHER
Whether something is a code or a cipher is a question that mainly vexes magazine editors looking at almost 4,000 words of copy in which the terms are used frequently, but the two concepts are not interchangeable.
One way of looking at it is that codes change words, but ciphers change individual letters, or bits. In the context of Lorenz, the Baudot code took the words that were enciphered letter by letter by letter by the
Geheimschreiber, and turned them into something else. Another approach is that ciphers are for keeping things secret, whereas codes can be publicly known. An example here is Enigma, which was meant to be secret until Bletchley Park got its hands on it, and which used Morse code to transmit gibberish to other Enigma operators, who then transformed it back into readable German through knowledge of Morse and the secret Enigma machine.
Roman dictator Julius Caesar, though not blessed with a wireless network through which to propagate his orders, made use of a simple substitution cipher in which letters are shifted a set number of places in the alphabet. So, with a shift of five, the common phrase “Maximum PC, Minimum
BS” becomes “Rfcnrzr UH,
Rnsnrzr GX.” You can see here an immediate weakness of a singlealphabet cipher: The words
“Maximum” and “Minimum” look very similar even when enciphered. A polyalphabetic cipher, such as Enigma or Lorenz, fixes this, but Enigma had a cryptographic weakness—no letter could ever be enciphered as itself— that Lorenz didn’t.