The number 404, the error message displayed when a browser cannot find a webpage, is now a part of the vocabulary of non-geeks as well, who commonly use this word to mean that you or the person you are referring to is clueless.
This was revealed by Jonathon Green, a British lexicographer who worked with the UK Post Office to come up a list [pdf] of slangs and acronyms from the cyber world that have crept into the English Language.
Some other words that are commonly used by people in the IT industry but that have now become part of our everyday language include:
Code 18 - Someone who is bad at using technology - IT people have traditionally used this phrase to refer to a problem which was the fault of the person using the computer. And since the user sits approximately 18 inches from the screen, it became a ‘Code 18′. This is used more widely in reference to a person who cannot use their own gadgets.
CGI Joe - Geek - In the IT industry, people who do the job of CGI script programming have an unfortunate reputation for being dull. In fact, they’re said to have as little charisma as a plastic doll – a CGI Joe. In popular language, this is now used by people to describe anyone who is a bit of a geek.
Meanwhile, there are other slangs like LAMP (Lost Another Million Pounds), which have nothing to do with the technical LAMP (Linux, Apache, MySQL, PHP).
Further reading: Don’t be 404, know the tech slang