Who was Albert Einstein and what are his achievements in life?

Albert Einstein was a physicist who developed the special and general theory of relativity. He is considered one of the most influential scientists of the 20th century.

 In 1921, he won the Nobel Prize for physics for his explanation of the photoelectric effect. In the following decade, he immigrated to the U.S. after being targeted by the German Nazi Party. 

His work also had a major impact on the development of atomic energy. In his later years, Einstein focused on unified field theory. With his passion for inquiry, Einstein is generally considered the most influential physicist of the 20th century. He is famous for his E = mc^2 energy mass equation.