A homomorphism between two sets preserves relations between elements. A set with a single operation (plus some extra properties) is called a group. The integer

A homomorphism between two sets preserves relations between elements. A set with a single operation (plus some extra properties) is called a group. The integers with addition (+) is an example of a group. Suppose I have groups X and Y. Then a group homomorphism, h, is a mapping at that preserves the + in the two groups, so h(x +_X y)=h(x) +_Y h(y) Where +_X is addition in X and +_Y is addition in Y. Homomorphic encryption means that what you used to do you encryption is a homomorphism.