Solving complex problems is always hard. Even for programmers, solving complex problems can prove tougher, and sometimes, a special solution is required. Recursion is one such special approach that computer programmers follow to solve complex problems. In this chapter, we will go through the definition of recursion, properties, different types of recursions, and lots of examples. Recursion is not a new concept; in nature, we see lots of recursive elements. Fractals show recursive behavior. The following image shows natural recursion: