Year 2000

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Year 2000

(Y2K, or "millennium bug") A common name for all the difficulties the turn of the century, or dates in general, bring to computer users.

Back in the 1970s and 1980s, the turn of the century looked so remote and memory/disk was so expensive that most programs stored only the last two digits of the year. These produce surprising results when dealing with dates after 1999. They may believe that 1 January 2000 is before 31 December 1999 (00<99), they may miscalculate the day of week, etc. Some programs used the year 99 as a special marker; there are rumours that some car insurance policies were cancelled because a year of 99 was used to mark deleted records.

Complete testing of date-dependent code is virtually impossible, especially where the system under test relies on other systems such as customers' or suppliers' computers. Despite this, the predicted "millennium meltdown" never occurred. Various fixes and work-arounds were successfully applied, e.g. time shifting.

And yes, the year 2000 was a leap year (multiples of 100 aren't leap years unless they're also multiples of 400).

This article is provided by FOLDOC - Free Online Dictionary of Computing (
References in periodicals archive ?
The site offers a fair and unbiased status report on the world's progress to eliminate or alleviate the Year 2000 problem and provides links to other Y2K sites and sources of information.
In sum, there is insurance coverage to pay for your company's year 2000 remedial activities and any future year 2000 losses, and you should pursue it.
In many cases, the year 2000 represents the date when the apocalypse purportedly will begin.
Addressing year 2000 problems is HCFA's top priority.
"The Year 2000 Date Problem--Support Centre: Is Your Hardware & Software Year 2000 Compliant?"
The Telco Year 2000 Forum was organized in 1996 to share information among local telephone carriers in preparation for the Year 2000.
Books on the topic include Capers Jones' 1997 work, The Year 2000 software problem (Addison-Wesley), and The Year 2000 software crisis by William M.
According to the SEC, Year 2000 disclosures are most appropriately made in the Risk and Uncertainties segment of the Management's Discussion and Analysis (MD&A) section of an annual report.
This limitation of liability for statements related to Y2K readiness was provided by Congress in the recently passed Year 2000 Information and Readiness Disclosure Act.
1) amounts contracted with outside parties as of fiscal year end to resolve Year 2000 issues;
Cosola cited research released by Gartner Group, of Stamford, Conn., which projects that 30 percent to 50 percent of businesses will experience failures of critical systems because of Year 2000 complications.
Commenting on the Senate bill, the Senate Judiciary Committee said the purpose of the act was to "help break the silence and encourage full disclosure and exchange of year 2000 computer problems, solutions, test results, and general readiness."[4] The bill was to provide "limited liability protection for a limited time for specific types of year 2000 information that is considered essential to remediation efforts."[5] However, Congress did not intend the act to "provide liability protection for failures that may arise from year 2000 problems."[6]