A nerve impulse is an electrical signal that travels rapidly along a nerve cell, carrying messages throughout your body. When you touch something hot, nerve impulses race from your fingertips to your brain in a fraction of a second, warning you to pull your hand away. When you decide to kick a soccer ball, nerve impulses zip from your brain down to your leg muscles, telling them exactly when and how to move.

Think of nerve impulses like tiny bursts of electricity speeding along biological wires. These signals move incredibly fast, some traveling over 250 miles per hour. Your nervous system sends millions of nerve impulses every second, coordinating everything from your heartbeat to your thoughts to the movement of your eyes as you read these words.

A nerve impulse works through a clever trick: nerve cells create the impulse by rapidly changing the electrical charge along their length, like a wave of electricity moving down the cell. Once a nerve impulse starts, it travels all the way to the end of the nerve cell without weakening, ensuring the message arrives intact. This is how your brain stays in constant communication with every part of your body, making you a coordinated, thinking, feeling person rather than just a pile of separate parts.