What Did Einstein Invent?
Albert Einstein worked in the fields of mathematics and physics, and most of his contributions were in terms of academic theory. There is, however, a refrigerator that bears his name, and he had also developed a compass, a gyrocompass and a hearing aid.
Albert Einstein is primarily known for contributing the theory of relativity as well as major contributions to the fields of statistical and quantum mechanics. The theory of relativity extended the existing equations by Maxwell to the laws of mechanics and explained how objects move through time and space. His contribution to quantum mechanics was to describe light according to Max Planck's quantum hypothesis, and his contribution to statistical mechanics was an experiment that supported the existence of molecules equivalent in size to the atom.
Einstein developed the Einstein refrigerator with Leo Szilard in 1926. It was created in response to news reports of a family who had died when their refrigerator seal developed a leak and toxic fumes filled their home. Einstein's refrigerator eliminated the possibility of seal failure by having no moving parts whatsoever. The refrigerator was an absorption model that required a heat source, which was common for the time, but was unique in using loops of ammonia and water for the cooling action. Though the refrigerator bears his name, it is unclear how much of it Einstein actually developed.