Christian broadcaster Harold Camping believes that he has calculated the exact date and time of the Rapture predicted in the Bible, and that day and time is 6pm tomorrow. He expects 200 Million people to ascend to Heaven while the remaining people on Earth will endure five months of tribulation before the world ends completely. Camping had made the same prediction that the rapture would occur in 1994 so his track record in terms of accuracy isn't the best.
Others believe that the world will end on December 21, 2012. That's the date that the Mayan calendar ends and some have speculated that it ends on this particular date for good reason. A handful of astronomers have calculated particular galactic alignments that could have catastrophic effects on the earth, and some physicists postulate that a massive solar flare could affect the earth's magnetic field to such a degree that the magnetic poles would reverse themselves, with the South Pole becoming the North Pole, and vice versa. New Age practitioners believe that the earth will collide with an as-of-yet unidentified planet. And then there are the folks who believe that 12-21-12 will be the date of a deadly alien invasion.
Throughout history, for as long as there has been civilization, there have been apocalyptic predictions foretelling the doom of those civilizations. These predictions are often tied with close passes from comets like Halley's in 1910 or the Hale-Bopp comet in 1997, or with the turn of a century or millennium. So far, none of the thousands of past apocalyptic predictions have come true. However, you never know when a major natural disaster, act of war, or other catastrophic event could occur, disrupting utilities and public services, breaking the supply chain, and basically making it difficult to survive if you aren't prepared.
Whether you give credence to apocalyptic predictions or not, we've seen in situations like Hurricane Katrina and the recent Japanese earthquake and tsunami, that being prepared for disaster is a pretty good idea. Even if you're 99.9% certain that nothing bad will happen, better safe than sorry! Start your disaster preparedness plan today, because you never know what tomorrow, or December 21, 2012, might bring.