It's Friday the 13th!

The superstition-laden phenomenon occurs at least once every year, but in 2010 and 2011, there was only one Friday the 13th. This year there are three, with one occurring in January, April and July.

Why so many this year? Is it some kind of 2012 curse? Not really; it's just how the calendar falls. There are two in 2013 (September and December), one in 2014 (June) then three again in 2015 (February, March, November). After that, there won't be another year with three until 2026.

Looking back though history, some unlucky events are believed to have occurred on Friday the 13th. French King Philip IV rounded up hundreds of monks and tortured them for heresy on Friday, October 13, 1307. More recently, on Friday, March 13, 1992, an earthquake in Turkey killed nearly 2,000 and left 50,000 homeless.

What's more, some people say Jesus Christ was crucified on Friday the 13th.

The number 13 has preoccupied people for centuries and psychiatrists even have a name -- triskaidekaphobia -- for the condition of intense fear of the number 13.

Take a look below at 13 examples of reactions to the belief that 13 is an unlucky number:

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  • No room in the inn

    Hospitals and hotels regularly have no room number 13.

  • On the street

    Many cities don't have a 13th Street or a 13th Avenue. This city tempted fate.

  • Blame your parents

    If you have 13 letters in your name, you're said to have the devil's luck. Like, this guy (Charles Manson).

  • Checking in

    Many airports skip the 13th gate.

  • Aisle omission

    Airplanes have no 13th aisle.

  • Numero...?

    Italians omit the number 13 from their national lottery.

  • Unlucky height

    More than 80% of high rises lack a 13th floor

  • One solution

    On streets in Florence, Italy, the house between number 12 and 14 is addressed as 12 and a half.

  • Hangman's noose

    Traditionally in hangings, there are 13 knots in the noose and 13 steps leading up to the moment of death.

  • Dinner luck

    French President Nicolas Sarkozy may know that in France, socialites called quatorziens (fourteeners) make themselves available as 14th guests to keep a dinner party from an unlucky fate.

  • Space travel

    Many say the No. 13 pointed to the ill-fated mission to the moon, Apollo 13.

  • It's in the cards

    Tarot Card number 13 is the Death Card, depicting the Grim Reaper.

  • Ancient ties

    Some say that the Babylonian Code of Hammurabi (circa 1780 B.C.E.) is to blame for the No. 13 woes since the 13th law is omitted.