A drag race is a competition where two vehicles race side-by-side in a straight line to see which one can reach the finish line first. Unlike regular races that involve turns and strategy, drag races are pure tests of acceleration and speed over a short distance, typically a quarter-mile (about 1,320 feet).

Drag racing began in the 1930s when drivers started racing their cars on empty streets and dry lake beds. Today it's an organized sport held at special tracks called drag strips. Professional drag racers drive specially built cars that can accelerate so quickly they need parachutes to help them stop safely. Some drag racing cars can go from zero to over 300 miles per hour in just a few seconds, which is faster than a roller coaster launch.

The starting line is called “the tree” because of the tall starting light system that counts down the race. When the green light flashes, both drivers floor it, meaning they press the accelerator all the way down. The winner is whoever crosses the finish line first, sometimes by just hundredths of a second.

People also use the phrase informally when two drivers pull up next to each other at a stoplight and accelerate quickly when the light turns green, but this is dangerous and illegal on public roads.