Peter Lynch is one of the most successful and well-known investors of all time. He is the legendary former manager of the Magellan Fund at the major investment brokerage Fidelity. He took over the fund in 1977 at age 33 and ran it for thirteen years. His success allowed him to retire in 1990 at age 46. His investment style has been described as adaptive to the prevailing economic environment at the time, but Lynch always stressed that you should be able to understand what you own.