Y2k - Numeronym

Y2K is a numeronym and was the common abbreviation for the year 2000 software problem. The abbreviation combines the letter Y for "year", and k for the SI unit prefix kilo meaning 1000; hence, 2K signifies 2000. It was also named the Millennium Bug because it was associated with the popular (rather than literal) roll-over of the millennium, despite the fact that the problem could have occurred at the end of any ordinary century.

The Year 2000 problem was the subject of the early book, Computers in Crisis by Jerome and Marilyn Murray (Petrocelli, 1984; reissued by McGraw-Hill under the title The Year 2000 Computing Crisis in 1996). The first recorded mention of the Year 2000 Problem on a Usenet newsgroup occurred Friday, January 18, 1985 by Usenet poster Spencer Bolles.[3]

The acronym Y2K has been attributed to David Eddy, a Massachusetts programmer,[4] in an e-mail sent on June 12, 1995. He later said, "People were calling it CDC (Century Date Change), FADL (Faulty Date Logic) and other names."

Many computer programs stored years with only two decimal digits; for example, 1980 would be stored as 80. Some such programs could not distinguish between the year 2000 and the year 1900. Other programs would try to represent the year 2000 as 19100. This could cause a complete failure and cause date comparisons to produce incorrect results. Some embedded systems, making use of similar date logic, were expected to fail and cause utilities and other crucial infrastructure to fail.

Some warnings of what would happen if nothing were done were particularly dire:

The Y2K problem is the electronic equivalent of the El Niño and there will be nasty surprises around the globe.