Day of the Beast End of Mayan Time Year 2038 Bug Planets Align Y2K Again
False Leap-Year Cover Page Index Appendix

Year 2100 Bug (Y2K again)

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Threat Level: Low

After the millenium came and went and planes didn't fall out of the sky, computer systems didn't shut down, and nuclear plants didn't experience a meltdown, we all thought that was the end of the Y2K bug. Unfortunately, it will come again.

Explanation

The Y2K bug occured when the year changed to 2000, and computer systems that saved the year as only a two digit number, would read 00 as 1900 instead of 2000.

Although Y2K has technically passed, an identical bug will appear the next time the year turns another century. Software that still keeps track of dates with only the last two digits will again, fail and assume the date to be 2000. For example, if a new program were created that will never involve dates before 2000, it would be relatively safe for the program to assume that any 2-digit year refers to the 20xx equivalent.

Another way in which Y2K may return to haunt us is when a "quickfix" method of fixing Y2K will fail. In layman's terms, it involves a programmer "fixing" the Y2k bug by telling computer programs to interpret any number from 0 to 60 (the exact number may vary) as the 20xx equivalent and any number between 61 and 99 as the 19xx equivalent. This fix would work for programs that will not need dates before 1961, however, the program will again break in 2061 when the program assumes the date to be 1961.

Consequence

Computer programs will assume the wrong date, and might either cease to function, or rollover to the old date representation (2000 in the case of the 2100 bug). The effect it will have depends on the function of the program and how the date is used. It will be unique on a case to case basis.

Consequences predicted are similar to those of Y2K. However, almost all programs will be largely unaffected unless the programmer is incompetant or the piece of software is not expected to be used up to that point anyway.