Recursion is a fundamental technique 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.

In computer science, a common method of simplification is to divide a problem into subproblems of the same type. As a computer programming technique, this is called divide and conquer and is key to the design of many important algorithms. Divide and conquer serves as a top-down approach to problem solving, where problems are solved by solving smaller and smaller instances. A contrary approach is Dynamic Programming. This approach serves as a bottom-up approach, where problems are solved by solving larger and larger instances, until the desired size is reached.