If you're tuning into the Olympic Games to catch up on snowboarding or figure skating, then you might be surprised to witness instead a mass of skiers sliding along with rifles on their backs. And you wouldn't be alone. Lots of people are wondering what a biathlon involves, because it certainly seems odd to stop a cross-country ski race, lie down in the snow, and shoot at targets. But there's actually a lot more to it than that — and it's actually pretty cool, when you think about the rules and the skill that's involved.

"This eccentric competition has been contested in various forms since the 18th century and has been part of the Olympics since 1924 (when it was known, more descriptively, as the military ski patrol)," Victor Mather noted on The New York Times. Unlike a decathlon, which has 10 events, or a triathlon, which has three, Mather said a biathlon has two: cross-country skiing and shooting.

And that's exactly what the athletes do. They ski from one target to the next with a rifle slung across their back, before aiming their guns, hitting a few targets, and then skiing on again.

"Biathlon ... is a standard cross-country ski race with periodic interruptions in which the athletes pull a .22-caliber rifle off their backs, point it at a target and shoot. Missed targets mean racers have to ski a 150-meter penalty lap," Mather told the Times. Which is why you see some skiers get up from shooting and ski on, while others have to do a few loops in a circle, first. They must ski the 150 meters, then try to catch up with their competitors.

When the shooters lie down to shoot, you'll spot five black dots on your TV screen representing the targets the athletes need to hit, which will blink out once the skiers make the shot. Because of this nifty guide, you'll be able to easily see who's firing straight and true, and who's missing their targets.

And that's what makes a biathlon more exciting, in many ways, than a traditional cross-country ski race. As Mather said, "... the shooting aspect is a wild card that throws every race in doubt until near the finish. A leader who misses a shot or three can fall well back because of the penalty loops. A skier who appears to be out of it can hit every target and vault toward the front."

So the gun aspect of the biathlon adds a bit of fun and mystery. But also, think about how difficult it would be to hold a gun steady and a shoot a target while you're out of breath from skiing. Adding guns into the mix ups the competition factor, as well as the skill needed to win. The athletes have to have incredible endurance, and a good eye.

As with many things at the Olympics, the sport is also richly steeped in tradition, which adds a third layer of interest. "The sport has its roots in hunting techniques that have been used in Scandinavian countries for centuries," Cork Gaines said on Business Insider. "Hunters would often take to skis with rifles mounted on their backs to find prey. These strategies were later used by the Swedish and Norwegian militaries. In fact, the first recorded biathlon competition occurred in the 18th century between the militaries of Sweden and Norway."

This sports goes way back. And it has a lot more going on than you might think. However "random" it may appear — the skiing, the guns, the target shooting — this sport may end up being your new fave.