Millennium bug is a term that refers to a problem that caused some computers to malfunction starting at midnight on Jan. 1, 2000. It is also called the year 2000 problem and the Y2K bug. The millennium bug affected not only computers but also other types of equipment that contained certain semiconductor chips produced before the 1990’s. Such equipment included fax machines, photocopiers, and burglar alarms. Failure of computers and other electronic equipment could have caused many problems for people, government departments, and many types of businesses. But people and organizations had prepared so well for the millennium bug that it caused few major problems.
The history of the millennium bug began in the early years of computers. The first computers had a limited capacity for storing information. In an effort to save as much storage space as possible, computer designers and programmers represented years using only the last two digits. For example, they used 67 for the year 1967.
Today, storage space on computers is much greater than it once was, and many computers and computer programs use the entire four-digit year. However, many older computers recognize only the two-digit year, and others run programs that do. The millennium bug caused some such equipment and software to interpret the 00 that represents the year 2000 as 1900 or as the year 0. Affected computers produced incorrect calculations or even shut down.
Some experts estimate that it cost hundreds of billions of dollars to solve the problem worldwide. Solutions to the problem included replacing computers that recognized only the two-digit year, removing from computers software that used the two-digit year, and altering files that were created by such software.
