Y2K: 10 years later

For anyone who needs an explanation after all these years, the Millennium Bug referred to computer systems that used two-digit dates because programmers at the dawn of computing did not think far enough ahead to put in four digits. So when the 1990s made way for the year 2000, the date, "99" would then become "00," with systems believing the world had just reverted to 1900 instead of advancing to the year 2000. "The fundamental issue was the date ranges," says Josh Aaron, president of Business Technology Partners, a technology consulting firm.

A now-retired technologist who worked for British Telecom 10 years ago recalls the extensive efforts to tend to Y2K. "It all got done, and it was a hell of a lot of work involved, and of course once you fix it, you've got to test it," says David Quinn, who ran the systems software group at BT.

Y2K was fixed because people prepared for it, Quinn says. "I wrote some of those systems" for billing and order management, he says. "I know the dates were wrong."

A decade after Y2K, technologists reflected back to InfoWorld on that time and the lessons learned, with some disagreement over whether Y2K turned out to be basically a nonevent because millions of dollars were spent in a heroic effort in advance to fix the problem or because the problem was overblown in the first place.

Was the Y2K Millennium Bug fear overblown "I think people felt duped because the world was predicting a disaster," Quinn says. There were even predictions that cars would stop running because of engine clock problems, he says.