What was the name of Daniel's mentor in "The Karate Kid"?

Learning martial arts isn't just about the moves but finding the right teacher. In 1984's "The Karate Kid," a bullied teenager discovers that sometimes the best mentors come in unexpected packages. Inside a humble apartment complex, he meets an unassuming maintenance man who would change his life forever. So who was the legendary teacher who turned Daniel LaRusso from prey to champion?