Do you avoid stepping on cracks in the sidewalk? Or have a lucky pair of socks that you wear during important meetings or when your favorite team plays in big games? Chances are, you follow at least a few superstitions at least superficially, especially if you're a sports fan.

So why do we do it? Why do we avoid black cats when crossing the street? Why do hockey players (and their fans) refuse to shave their beards until their team has been eliminated from the playoffs? And why do you freak out if you can't find that lucky pair of socks before that big meeting?

There are three likely reasons:

Superstitions helped us survive. "Many superstitions have a basis in reality," says holistic physical therapist Sally Morgan. From a safety standpoint, a lot of classic superstitions such as not walking under a ladder, avoiding cracks in the sidewalks, or not opening umbrellas indoors are just common sense ways to avoid injury. As Morgan explains, even when these superstitions no longer apply to modern life, our belief in them sticks around because at one point, these daily rituals helped us survive.

They help us cope. Superstitions can help us deal with situations that we feel are out of our control. In this way, we are comforted by putting our faith in something, because even a false sense of security is better than no security at all.

For example, let's say you wore a new tie on the day of a big meeting that didn't go well. It's easier to blame the tie and dub it "unlucky" than to accept the fact that some other factor caused the meeting to fail. And let's face it, the mind is a powerful force. If you believe that your tie is unlucky, you will be more likely to attribute any negative outcome (such as your car breaking down or a fight with your partner) to that unlucky object, thereby perpetuating the superstition in your head.

So when you avoid wearing that tie — or steer clear of the path of a black cat — you may feel like you're controlling your destiny by making it less likely that something bad will happen to you.

Woman crossing fingers In one study, participants who were told that the researcher would 'cross their fingers for them,' performed better on tests than those who were not given this affirmation. (Photo: WAYHOME studio/Shutterstock)

They give us something to believe in. Just as we are quick to blame inanimate objects for our bad luck, we are quick to attribute good luck to outside forces as a way to help us control that luck in the future. And just as we can perpetuate the belief that a certain item is responsible for anything negative that comes our way, we can actually improve our chances of success when we believe in the power of a good luck omen.

A 2010 study published in the journal Psychological Science found that good-luck superstitions do lead to increased confidence which can then translate into a better outcome. When students in the study were allowed to bring their good-luck omens with them during a series of tests, they set higher goals for what they hoped to achieve on the tests and reported feeling more confident in their abilities than those who didn't have a talisman.

Athletes use these kinds of good luck rituals all of the time. Olympic runner Shalane Flanagan finds good luck in the number 8 as this was the number on her bib when she took home the silver in the 10,000 event at the 2008 Olympics. So it's not unusual for her to seek out a hotel room on the eighth floor or request that the number 8 be present on her bib for big races.

And here's a look at the eight-step ritual performed before every game by Corey Perry, a star hockey player from the Anaheim Ducks.

Of course, Flanagan knows that having a room on the eighth floor won't make her run any better at a race, just as Perry probably knows that none of these moves will help him perform better on the ice, but it's their belief in the overall power of these routines that can give them the extra confidence boost they need to outmatch their opponents. And it's that confidence that might just help them secure the win.

Why are we so superstitious?
Superstitions have power because we believe in them. Here's why.