Brian Cryer's Web Resources

Y2K Problem

Y2K Problem
A perceived IT problem when year rolled over from 1999 to 2000.

The Y2K problem was one of storage, format and hype:

  • Storage. In order to save on space many early computer systems only stored two digits for the year portion of a date. When storage was expensive savings of one or type bytes per record especially over a large number of records was significant. The problem with the year 2000 is that many of these storage techniques would not handle the roll-over from 99 to 00.
  • Format: Many systems display the year component of a date as two digits. (This was common before the year 2000 and is still common today.) For systems that were written assuming the year was nineteen hundred and something, the change of date format to twenty-something represented a problem. It was not uncommon for some systems (and websites) in early 2000 to display the date as 19100 because they did not handle the format correctly.
  • Hype. There was considerable media hype and doom-mongering before the year rollover from 1999 to 2000. There was also considerable expense invested by many companies to ensure that it would not be a problem. There were even rumours that some multinational corporations had teams of developers standing by to tackle last minute problems in each time zone, so as the year changed in one time zone those in later time zones would have a few final hours to fix any problems that arose.

In reality when the year transition finally happened from 1999 to 2000 other than new year parties the new year passed almost without incident. These days it is a moot point of discussion whether too much attention was paid to the Y2K problem or whether it was not a problem because so much attention was paid to it.