Archimedes was many things, he was a mathematician, a physicist, a engineer, an astronomer, an inventor, and a scientist. He is considered the to be the greatest mathematician of time. He also figured out that the kings crown was not only made of pure gold, but it also had silver in it.
He and his followers were the first to describe many disease and medical conditions. He was the first person to believe that diease came naturally, not because of the gods. He lived at the "The Golden Age of Greece.
Not much is known about this man. He is known as the "Father of Geometry". He was a great thinker though.
He believed that the planets and stars were laid out in mathematical precision and that they created music. The Pythagorean theorem was known and used by Babylonians. We don't use much associated with him, but he developed and taught them.