What groundbreaking scientific theories did Einstein develop that you need to know about?

Albert Einstein developed the theory of relativity, which revolutionized our understanding of space, time, and gravity. This theory consists of two parts: special relativity and general relativity. Special relativity explains how time and space are intertwined and how they can be affected by motion. General relativity extends this to include the effects of gravity on the fabric of space-time. These theories have had a profound impact on physics and our understanding of the universe.