Kids are afraid of things like monsters and ghosts. For adults, it's things like death and losing their job that strike fear.
But what about the sports world?
In honor of Halloween, here's a list of the most frightening scenarios from the world of sports.
No. 10: Ski jumping
Why it's scary: Barreling down a ramp at about 75 mph and launching over 300 feet in the air is enough to make even adrenaline junkies think twice. Watch the "agony of defeat" at the opening of ABC's Wide World of Sports and you'll know what we're talking about.
No. 9: Facing Randy Johnson
Why it's scary: The Big Unit has had troubles with control in the past and isn't as sharp as he once was, leaving open the possibility that he might whiz one at your earhole.
No. 8: Taking a hard foul from Shaquille O'Neal
Why it's scary: The problem with this one is that you might get squished by one of the world's biggest men. At 7 feet, 325 pounds (a low figure, by most accounts), the Miami Heat center doesn't do anything soft.
No. 7: Getting hit into the boards by Todd Bertuzzi
Why it's scary: For one, the dude's huge at 6-foot-3, 245 pounds. And Bertuzzi, now playing for the Florida Panthers, also has a bit of a nasty streak. Just ask Steve Moore. The former Colorado Avalanche player has yet to return to the ice after being leveled by Bertuzzi two years ago on a hit that led to assault charges in Vancouver.
No. 6: Driving an Indy car
Why it's scary: The 200 mph part should be enough to scare anyone away. But the reason Indy cars get the scary nod over NASCAR is the build of the car. Have you ever seen one of those things launch into the air? It's like a paper airplane catching a drift and flipping over.
No. 5: Launching off a mega ramp on a skateboard
Why it's scary: This one might not be familiar to the non-X Games crowd, but that doesn't make it any less scary. If you haven't seen it, the mega ramp looks like a Six Flags ride, only without anything to strap you in.
No. 4: Getting hit by Ray Lewis
Why it's scary: He's big, he's mean, and he's one of the best players in the NFL. You get the impression that Lewis likes hurting people. The Baltimore Ravens linebacker gets worked up for a game like he's going to war and treats everyone like the enemy.
No. 3: Driving a Top Fuel dragster
Why it's scary: Maybe it's just us, but there's something about going 330 mph that doesn't seem right. Planes go that fast, but at least those are thousands of feet above the ground, skewing the speed perspective.
No. 2: Surfing the Jaws wave
Why it's scary: For the uninitiated, Jaws is the epitome of big-wave surfing, a section of the Pacific Ocean where waves about the size of seven-story buildings crash along the north shore of Maui. Wipe out on one of these monsters, and there's a good chance you won't be coming up from the crush of whitewater.
No. 1: Stepping into the ring with Mike Tyson
Why it's scary: The guy might be washed up as a professional fighter (his latest exhibition tour has a Barnum & Bailey feel), but Iron Mike can still throw a punch that would knock most of us senseless. What makes him so scary is that "he's not right in the 'ead," to quote one of our favorite lines from "Braveheart."