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10 Scare-inducing Moments in History

Perhaps more frightening than Y2K is the size of our old computer monitors. Photodisc/Getty Images
Perhaps more frightening than Y2K is the size of our old computer monitors. Photodisc/Getty Images

The Y2K bug was big news in December 1999. Dire predictions of accidental missile launches, nuclear meltdown, financial panic and airplanes falling from the sky had people building bunkers and stocking them with Spam. Wilderness-survival boot camps recruited participants like never before. Even the venerated Time magazine set up a generator-powered "war room" in the basement of their building. Despite reassurances from experts, people were worried. So what was this Y2K bug, and why was it turning otherwise normal people into end-of-timers?

Y2K was a computer bug. A completely avoidable computer bug. The whole problem started back in the 1960s when computer programmers, concerned about expense and limitations of digital storage, wrote code that only allowed two digits for the year. So "10/15/1965," for example, would simply be coded as "10/15/65." Everything was fine until the 1990s, when concern grew that computers might interpret the looming year 2000 — known in computer-speak as "00" — as 1900. Calculations for everything from interest rates at banks to safety checks at nuclear power facilities would be incorrect. In preparation, the United States spent millions of dollars updating military, transportation and financial computer systems [source: Rothman]. Still, the problem played on people's lingering fear of technology, and the belief among some Christians that Jesus might return 2,000 years after his birth only escalated the concern [source: Sheesley].

On Dec. 31, 1999, people watched with a little more anxiety and a little less celebration as the clock ticked towards potential Armageddon. Then, at midnight, nothing happened. Aside from a few minor, isolated incidents, everything was fine. Countries that didn't prepare were no worse off than those that did. And everyone breathed a collective sigh of relief [source: National Geographic].

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