overview

Electricity

Electricity is a basic feature of the matter that makes up everything in the universe. When most people hear the word electricity, they think of lights, television, microwave ovens, computers, air conditioners, and other electrically powered devices. Electricity makes these and many other useful things possible. But electricity is much more important than that. Electricity and magnetism together make up a force called electromagnetism, one of the fundamental forces of the universe. Electrical force is responsible for holding together the atoms and molecules from which matter is composed. In this way, electricity determines the structure of every object that exists.

Electricity is also associated with many biological processes. In the human body, electrical signals travel along nerves, carrying information to and from the brain. Electrical signals tell the brain what the eyes see, what the ears hear, and what the fingers feel. Electrical signals from the brain tell muscles to move. Electrical signals even tell the heart when to beat.

One of the most important properties of electricity is electric power. During the 1800's, people learned to harness electricity to do work. This new source of power had so many practical applications that it greatly changed the way people lived. Inventors and scientists learned how to generate electric power in large quantities. They found ways to use that power to produce light, heat, and motion. They developed electric devices that enabled people to communicate across great distances and to process information quickly. The demand for electric power grew steadily during the 1900's. Today, most people cannot imagine life without electric power.

Excerpt adapted from the "Electricity" article, The World Book Encyclopedia © 1999