Considered by many to be the greatest scientist of the 20th century, being named by Time magazine as "Man of the Century".
A physicist, he won a Nobel Prize for his discovery of the photoelectric effect (1905), which explained how a photon causes an electron to be emitted from a metallic surface when illuminated by light, by postulating that photons are discrete "quanta" of energy.
He also devised the Theory of Special Relativity (1905), which deals with the perception of time and distance between observers in different frames of reference that are moving relative to each other, and postulated that the speed of light is the same in all frames of reference.
Later he expanded this into the Theory of General Relativity (1907), which explains the force of gravity as a geometric warping of space-time and treats acceleration and gravity as equivalent forces acting on matter.
Born a Jew in Germany, he came to America just prior to the Nazi's rise to power (1932), and never returned to his homeland.
He spent the last years of his life attempting to combine the fundamental forces into a single unified field theory, but without success.
Ironically, his name is used as a derogatory term for persons who proclaim something obvious or who do something especially stupid.
That was a really smart move, Einstein!
*A name used to relay something obvious toward one who seems to not have the common knowledge.
"Hey Einstein that was a civilian! *slaps him upside the back of the head*"