Locomotion is the act of moving from one place to another under your own power. Animals use different forms of locomotion: birds fly, fish swim, snakes slither, and humans walk.

When scientists study locomotion, they examine how different creatures have evolved unique ways of getting around. A kangaroo's hopping is a form of locomotion perfectly suited to covering long distances across Australia's open plains. A cheetah's sprinting locomotion makes it the fastest land animal. Even tiny ants have their own form of locomotion, scurrying on six legs.

Humans have also invented machines for locomotion. Steam locomotives were massive engines that pulled trains across continents in the 1800s. Before cars and planes existed, these locomotives revolutionized travel, turning journeys that once took weeks into trips of just days.

You might encounter this word in biology class when learning how animals move, or in history when studying transportation. When you run across the playground, climb a tree, or swim at the pool, you're using different forms of locomotion.