Stephen Hawking grew up near London, a city in England. He was good at math and science. He went to college and then became a scientist. Hawking is disabled, so he works from a wheelchair and uses a special computer.
As a scientist, Stephen Hawking studies the universe. He asks hard questions, such as how did time begin? How big is space? Will the universe ever end? He tries to find out the answers to these questions.
Hawking wrote a popular book about how scientists try to answer these questions. It is called A Brief History of Time. It helps people who are not scientists understand the way the universe works.
Why do you think A Brief History of Time is a popular book?