A bobsled is a sleek racing sled designed to hurtle down icy tracks at thrilling speeds. Picture a streamlined metal tube on runners, built to carry a team of two or four athletes who work together to pilot it through a winding, banked course. The sport got its name from the way early riders would bob their bodies back and forth to increase speed.

Bobsledding is one of the most exciting events in the Winter Olympics. Teams sprint alongside their sled at the start, pushing it as hard as they can before leaping in. Then they're flying down an icy chute at speeds over 90 miles per hour, experiencing forces that press them into their seats with several times their normal weight. The driver steers using subtle rope pulls connected to the front runners, while the brakeman in back uses a lever to slow down at the finish.

The tracks themselves are architectural marvels: twisting tubes of ice with walls so steep that sleds ride nearly sideways through the turns. A single mistake, a bad push, or a slight steering error can cost a team the race, since victory margins are often measured in hundredths of a second.