Albert Einstein (1879-1955) is one of the greatest scientists of all time. His ideas changed the way other scientists think about time, space, motion and gravity. (Gravity is the natural force that pulls things down toward the surface of the Earth.) He helped people understand how things work together.

Einstein became interested in science when he was a child. He was only 5 years old when his father showed him a compass. (A compass is used to find directions. It has a needle that always points to the north.) Einstein thought the compass was a mysterious instrument because the needle kept pointing in the same direction no matter which way he turned it.

As a young man, Einstein was able to explain difficult scientific ideas. By the time he was 26 years old, he had already developed the idea for which he is best known. This idea is called the theory of relativity. In 1921, Einstein received a Nobel Prize, an important award, for a paper he wrote.

Einstein was born in Europe and grew up there. He became a professor. In the middle of his life, the Nazi government of Germany took away Einstein's property and his job. Einstein then settled in the United States and later became a U.S. citizen.

A quiet person, Albert Einstein had many interests besides science. He enjoyed classical music, and he played the violin. He always cared about people who were less fortunate, and he never tried to make a lot of money. He married twice. He had two sons, one daughter and two stepdaughters.

How to cite this article: To cite this article, World Book recommends the following format: "Albert Einstein." The World Book Student Discovery Encyclopedia. Chicago: World Book, Inc., 2005.