Albert Einstein (1879-1955) was a German-born physicist and is still seen as a giant in the field of physics, even 70 years after his passing.

That’s in large part due to his theory of relativity. Einstein first published the theory in 1905 and it introduced the world to the idea that mass and energy can be converted into each other if the circumstances are right.

But don’t take our word for it. Listen to Einstein explain it himself in this footage!