Sir Isaac Newton was one of the greatest scientists of all time. He is mostly known for his early theories of gravity, but also for his discovery of the three laws of motion.
Newton's three laws of motion are found in his book Principia, which was published in 1687. The laws of motion are: One, a still object will stay at rest unless acted upon by an unbalanced force, and a moving object will stay in motion at the same speed unless also acted upon by an unbalanced force; two, acceleration is produced when a force acts on a mass. The bigger the mass, the greater amount of force needed to accelerate the object; and three, for every action, there is an equal and opposite reaction. Newton's three laws of motion helped people figure out how the universe works.
Newton was born on Christmas day in 1642. He was born a premature infant--so frail he was not expected to live. His father died before he was born and, when he was just 18 months old, his mother remarried a rich minister and left him to grow up at his grandparents’ house. This big event sparked a deep anger in Newton, which he bottled up for most of his life, making him a difficult man to deal with.
Newton later joined Cambridge University where he was a below average student. He almost dropped out of college, but a teacher recognized his mathematical gift and tutored him. Soon, Newton developed into a proficient student. He studied and read Copernicus and Galileo.
In 1665, Cambridge closed down due to the bubonic plague, so Newton returned to his hometown, Woolsthorpe, and stayed for a year. With all the peace he had by himself, he developed more theories. Including the theory of gravity. During this period Newton reconstructed the telescope into a smaller, more accurate version. That telescope got him into the respected and honored Royal Society, which was the leading scientific organization in Europe.
After returning to Cambridge, Newton published several books filled with revolutionary theories about science and mathematics. Later in life he was awarded the high honor of working at the Royal Mint and was also knighted by the Queen of England.
Students nowadays may take the scientific laws like gravity and motion for granted, but in Newton's day these were intriguing and amazing discoveries. Newton died on March 20, 1723. After attending his funeral, the philosopher Voltaire said “England honors a mathematician as other nations honor a king who has done well by his subjects.”
[Sources: : Physics4kids.com; History: The Modern Era; The Great Scientists: From Euclid to Stephen Hawking]