Are you inexplicably terrified of bad things happening to you on Friday the 13th? Yes? Then I have unfortunate news, my friend: You have paraskavedekatriaphobia, which is the impossible-to-pronounce way of saying you have a fear of this ~cursed day~. But do you even know what you're so freaked out about? Probably not if you're reading this, so it's time to find out if your iffy feelings are legit.
FIRST OF ALL, WHAT'S WRONG WITH 13?
Poor thirteen has been considered a sinister number for a long time—ever notice how there's no thirteenth floor in most buildings? Apparently, the dislike of this long-maligned number goes all the way back to Jesus' last supper. As University at Buffalo professor Phillips Stevens, Jr. put it: "There were 13 people at the table (at the Last Supper) and the 13th was Jesus." You'd think a number associated with JC would be considered lucky, but keep in mind that he was crucified the very next day.
For what it's worth, my favorite theory is that the fear stems from the fact that it takes *13* witches to form a coven. Just saying.
WHY FRIDAY, THO?
Some people think that Friday the 13th specifically became unlucky after Philip IV arrested a ton of Knights Templar (many of whom were later killed) on this day in October 1307. But come on, those people probably spend a lot of time reading Dan Brown novels. Just! Saying!
But yes, the origin story lively involves religion in some way. The Crucifixion did happen on a Friday, after all. I'll let Professor Stevens explain: "The Last Supper was on a Thursday, and the next day was Friday, the day of crucifixion. When '13' and Friday come together, it is a double whammy for people who have these kinds of magical beliefs." Additionally, people don't like Fridays because during ye olden medieval times, Fridays were "hangman's days," as in, literally the day during which people who were condemned to death would be hanged. Yikes.
So basically people have thought Friday the 13th was shady AF for a long, long, loooOOOoOOOOooOOong time, though the movie (featuring everyone's favorite terrifying serial killer Jason) certainly helped push the unlucky date into the public consciousness.
BUT DOES BAD STUFF ACTUALLY GO DOWN ON FRIDAY THE 13TH?
Per the BBC, there are more traffic accidents (at least in England) on Friday the 13th. That said, chances are you can go about your life as usual without something bad *actually* happening to you. Still, you might want to watch out for black cats, refrain from walking under ladders, resist the urge to open umbrellas inside, and—whatever you do—do NOT break a mirror.
WAIT—SO IT REALLY HAS NOTHING TO DO WITH THE MOVIE?
Correct. The Friday the 13th film franchise, which started with the O.G. 1980 Sean S. Cunningham slasher flick, centers on the story of Jason, an 11-year-old kid who drowned at summer camp because his counselors were too busy having sex to save him. His mom avenges his death by killing a bunch of teenagers also having sex. It's unclear if it this all went down on Friday the 13th—OK, I didn't watch it; sue me—or how the hell Jason comes back to life as an adult to become the murderer in the next 11 movies. In short: a guy in a hockey mask will not show up at your door on Friday, the 13th. Probably.
WHEN IS THE NEXT FRIDAY THE 13TH?
The good news is that 2018 is fully done with Friday the 13ths. So the next cursed day you have to worry about is September 13, 2019, and December 13, 2019. Meanwhile, in 2020, there will be one on March 13 and another one on November 13. So prepare yourself to read into every single bad thing that happens to you those days!
This article originally appeared on Cosmopolitan.com. Minor edits have been made by the Cosmo.ph editors.