In mathematics and abstract algebra, group theory studies a type of algebraic structure called a group. Group theory is often used in mathematics as a starting point for the study of many algebraic structures, and of addition and multiplication of numbers. Because group theory is also useful for studying symmetry in nature and abstract systems, it has many applications in physics and chemistry.
== Definition ==
A group is a set (collection) G whose members are called elements. The elements can be numbers of some kind, or other abstract objects. The elements can even be material objects. There is...