Richard Feynman is a rare person who had both a sense of humor and also was an amazing scientist. He was instrumental in such events as inventing the atom bomb and also discovering the cause of the Challenger spaceship explosion. Feynman was a key scientist in the study of quantum physics, which explains the behavior of miniscule particles. While at Cornell University Feynman worked on an explanation for how particles interact with each other. He calculated all the possible ways a particle could move between two points, this is the path integral. He then created a graph that would calculate a particles path integral in both space and time showing how the particle moves. This graphic is appropriately called a Feynman Diagram.
Some interesting personal information about Feynman: He was rejected from the World War II draft for mental reasons. Apparently, he was too literal in the interview. He performed in the student production of South Pacific at Caltech. He was an expert safe cracker.