Here's the worst case scenario: a black cat crosses your path as you walk under a ladder to pick up the pieces of the mirror you've just broken.
That's the ultimate superstition nightmare for those who believe this day — Friday the 13th — is nothing but bad luck. Of course, the experts will tell you that there's nothing to it. But some will always believe otherwise.
There are three such dates in 2012, beginning with today. The next two fall in April and in July—exactly 13 weeks apart. There was only one such date last year.
Friday the 13th isn’t an unlucky day in Port Dover, Ont., where thousands of motorcycle enthusiasts gather for a day-long celebration in the town on the shores of Lake Erie.
The tradition started in 1981 and the snowy weather isn’t expected to deter bikers. The Friday the 13th rallies can generate up to $2 million for Port Dover and Norfolk County.
While it's hard for some to take Friday the 13th seriously, the myth persists.
There's even a scientific name for it — triskaidekaphobia, fear of the number 13. And then there's paraskevidekatriaphobia, an actual fear of Friday the 13th itself.
So where did it all begin? Like most legends, the actual origin is lost to history. But scholars who've studied the phenomenon believe there are Biblical connotations.
"Friday was the day on which Christ was crucified. ... Judas was considered the 13th person at the table [of the Last Supper] and he of course, is the betrayer," Dena Taylor, a University of Toronto occult expert, said.
She noted Christians in the Middle Ages also believed witches met in covens of 13 — and the 13th member was the devil himself.
Another theory about the origins of Friday the 13th relates to the Knights Templar — a powerful group formed during the Crusades. France’s King Philip IV is said to have ordered the mass arrest of templars on Friday, Oct. 13, 1307.
For people in other parts of the world, Friday the 13th is simply the name of a series of horror movies.
"Within western culture Friday the 13th is perceived as being unlucky. ... [In other cultures] it's meaningless," Taylor said.
With files from 680NEWS