Recursion occurs when the definition of a concept or process depends on a simpler or previous version of itself.[1] Recursion is used in a variety of disciplines ranging from linguistics to logic. The most common application of recursion is in mathematics and computer science, where a function being defined is applied within its own definition. While this apparently defines an infinite number of instances (function values), it is often done in such a way that no infinite loop or infinite chain of references can occur.
A process that exhibits recursion is recursive. Video feedback displays recursive images, as does an infinity mirror.