Watch Albert Einstein Explain His Theory of Relativity in Historic Footage

You may have learned about the theory of relativity—or at least seen E = mc² scribbled on a chalkboard somewhere—but nothing compares to hearing Albert Einstein explain it in his own words. In this historic footage, you can watch the theoretical physicist describe the concept that made him famous.

First published in 1905, Einstein's theory of special relativity had an enormous impact on how we study the universe. It introduced the famous equation E = mc², or energy equals mass times the speed of light squared. In simplified terms, special relativity states that mass and energy are the same thing in different forms, and one can be converted to the other—or vice versa—under the right circumstances.

You don't have to be a master of theoretical physics to enjoy the video below. If you've only seen photos of Einstein (with or without his tongue sticking out) or read his brilliant quotes, this footage offers a fascinating glimpse of the man behind the famous theories. No matter your grasp on the subject, hearing him speak is captivating.

When Einstein died in 1955, he left behind a legacy that continues to shape the world of science world. Here are some facts about the fascinating figure.