The prefix "cyber-" is now a handy way of denoting words to do with the internet - from cybercrime, cyberbullying and cybersecurity to improbable activities such as cybersnogging. It followed an eventful path to reach its modern meaning,
In ancient Greek kubernao meant "steer a ship" and kubernetes was a steersman. Homer tells how the gods smote Odysseus's ship, so that the toppling mast crushed the steersman's head (kuberneteo kephalen).
The normal Latin transliteration of kubernetes gives us "cybernetes" - though practical seafaring Romans worried less about the rules and turned kubernao into guberno, from which we get "govern".
Plato used "kubernetika" to mean skill in steering, and in the 1940s the American mathematician, Norbert Wiener, derived from it "cybernetics" to mean "control and communication theory, whether in the machine or in the animal".
In the popular imagination the term cybernetics and therefore cyber- became associated especially with humanoid robots, or similar controlled creatures such as the Cybermen, who first appeared in Doctor Who in 1966.
In The Hitchhiker's Guide to the Galaxy (1978) the Sirius Cybernetics Corporation calls a robot "Your Plastic Pal Who's Fun To Be With".
The progression from ancient helmsman to comic robot is clear enough and the common theme is control. But how did cyber- go on to its present association with the internet?
The link is the term "cyberspace" - the virtual electronic world in which we explore, play, learn and share information.
Theoreticians of cyberspace such as Howard Rheingold acknowledge that the word comes from the science fiction writing of William Gibson, particularly his 1984 novel Neuromancer.
Its hero longs to return to the online world from which he has been banished, and the book lyrically describes virtual reality folding "through a dozen impossible angles, tumbling away into cyberspace like an origami crane".
But Gibson's account of how he coined the term cyberspace contains a lesson for anyone who reads too much into the derivations of words.
He tells how he needed a "really hot name" for the arena in which his stories would be set, and cyberspace "sounded like it meant something or it might mean something, but as I stared at it, my whole delight was that I knew it meant absolutely nothing".
If he had fancied instead something like "infosphere" or "digiworld", our terminology might be very different.
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