Einstein didn't discover gravity itself, as that was already understood through Newton's Law of Universal Gravitation. Instead, he revolutionized our understanding of gravity with his theory of General Relativity. Here's what he proposed:

* Gravity is not a force, but a curvature of spacetime: Imagine a stretched sheet. A heavy object placed on it will create a dent. This dent is like the curvature of spacetime caused by massive objects. Objects move along this curvature, giving the illusion of a force pulling them towards the massive object.

* Gravity affects the path of light: Light, which was thought to travel in straight lines, is actually bent by the curvature of spacetime around massive objects. This was confirmed by observations during solar eclipses.

* Time is relative to gravity: Time slows down near massive objects due to the stronger gravitational pull. This effect is known as time dilation.

In essence, Einstein's theory of General Relativity painted a much richer picture of gravity than Newton's theory. It explained more phenomena, like the precession of Mercury's orbit, and led to new predictions, like the existence of black holes and gravitational waves.