Friday the 13th...

Well the day has just begun and as we all know many people are very much superstitious about this day. From the horror movie of the same name to the person who tells you not to walk under that ladder to the black cat that stares at you while you walk to the train station on your way to work, today - Friday the 13th, is a day of fear for some. But what is this day all about anyways?

Friday the 13th occurs when the thirteenth day of a month falls on a Friday, which superstition holds to be a day of bad luck. In the Gregorian calendar, this day occurs at least once, but at most three times a year. Any month's 13th day will fall on a Friday if the month starts on a Sunday.

The fear of Friday the 13th is called friggatriskaidekaphobia, frigga meaning "Friday" and triskaidekaphobia (or paraskevidekatriaphobia) being a word derived from the concatenation of the Greek words Paraskeví (Παρασκευή, meaning "Friday"), and dekatreís (δεκατρείς, meaning "thirteen") attached to phobía (φοβία, from phóbos, φόβος, meaning "fear"). The word was derived in 1911 and first appeared in a mainstream source in 1953.

According to folklorists, there is no written evidence for a "Friday the 13th" superstition before the 19th century. The earliest known documented reference in English occurs in an 1869 biography of Gioachino Rossini:

[Rossini] was surrounded to the last by admiring and affectionate friends; and if it be true that, like so many other Italians, he regarded Friday as an unlucky day, and thirteen as an unlucky number, it is remarkable that on Friday, the 13th of November, he died.

One theory states that it is a modern amalgamation of two older superstitions: that thirteen is an unlucky number and that Friday is an unlucky day.

In numerology, the number twelve is considered the number of completeness, as reflected in the twelve months of the year, twelve signs of the zodiac, twelve hours of the clock, twelve tribes of Israel, twelve Apostles of Jesus, twelve gods of Olympus, etc., whereas the number thirteen was considered irregular, transgressing this completeness. There is also a superstition, thought by some to derive from the Last Supper or a Norse myth, that having thirteen people seated at a table will result in the death of one of the diners.

Friday has been considered an unlucky day at least since the 14th century's The Canterbury Tales, and many other professions have regarded Friday as an unlucky day to undertake journeys or begin new projects. Black Friday has been associated with stock market crashes and other disasters since the 1800s. It has also been suggested that Friday has been considered an unlucky day because, according to Christian scripture and tradition, Jesus was put to death on a Friday.

Some events are intentionally scheduled for Friday the 13th for dramatic effect. They include:

Resident Evil 5 was released in the US and UK on Friday March 13, 2009.

SAW - The Ride at Thorpe Park, UK was opened on March 13, 2009. Coincidentally the ride was marred by "teething problems" for the first few days after it was opened

Black Sabbath's eponymous debut album was released in the UK on Friday, February 13, 1970.

The Opening ceremony of the Athens Olympic Games took place on Friday, August 13, 2004.

The 13th book in A Series of Unfortunate Events was released on Friday, October 13, 2006 by Lemony Snicket, also known as novelist Daniel Handler.

Four of the twelve films in the Friday the 13th series, including the most recent (reboot of a second film), were released on a Friday the 13th. The sequel to the reboot is planned to be released on Friday September 13, 2013.

Joss Whedon's show Dollhouse aired its pilot on February 13, 2009.

Every Friday the 13th thousands of bikers ride to the small town of Port Dover Ontario, Canada.

Boston Lee Day is celebrated every Friday the 13th. Participants gather to enjoy the Boston Lee Drink for which this day is named.

The popular Browser-based RPG Dragonfable has an undead war every Friday the 13th, with a common drop being the hockey mask all of the monsters wear.

The 2009 film 2012 was released on Friday November 13, 2009.

Stuntman Sam Patch scheduled a 125-foot jump into the Genesee River on Friday, November 13, 1829, his largest jump to date. The jump killed him.

Due to the large number of events that happen in the world, a similar list could be compiled for any combination of day of the month and day of the week. Events that have been notable for being linked to the concept of Friday the 13th include:

Hurricane Charley made landfall in south Florida on Friday, August 13, 2004.

The "Friday the 13th Storm" struck Buffalo, New York on Friday, October 13, 2006.

The asteroid 99942 Apophis will make a close encounter with Earth, which had been thought may have been closer than the orbits of communication satellites, on Friday, April 13, 2029.

The Andes Plane Crash of 1972 occurred on Friday, October 13, 1972.