Sir Isaac Newton is best known for explaining how gravity works. Newton was born in Woolsthorpe, England on January 4, 1643. As a child, he loved to make model windmills and other mechanical toys, but he did badly in school and even worse running the family estate.

At the University of Cambridge, both the students and professors disliked him because of the chip on his shoulder. He was about to quit when one of his professors recognized the genius behind his rude behavior and became Newton’s special tutor.

It was while he was on a break from Cambridge that Newton started thinking about gravity. Scientists already knew such a force existed, but Newton found the formula to describe how much force any two bodies will exert on each other. Since he couldn’t prove his theory with the mathematics available, he invented calculus to do it for him. He explained the mathematical theory on tides under gravitational pull from the sun, moon and earth. He discovered the secrets of light and color and showed how the universe is held together. He made all of those amazing discoveries within 18 months, between 1665 and 1667, though he didn’t publish his theory on how gravity works until 1687. Some people call that book, The Principia, the greatest scientific book ever written. He also invented the reflecting telescope.

Newton was knighted by Queen Anne and became Sir Isaac in 1705.