Method of solving a problem where the solution depends on solutions to smaller instances of the same problem (as opposed to iteration). In programming terms, recursion is when a function calls itself during execution. Recursion is fundamentally connected to the concept of fractals.

Example: computing factorial

function factorialize(n) {
  if(n < 0) {
    return -1;
  } else if(n == 0) {
    return 1;
  } else {
    return n * factorialize(n - 1);
  }
}

Articles:

• Recursion on Wikipedia
• Recursion (computer science) on Wikipedia
• Droste effect on Wikipedia