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Recursion

The definition of the word recursion is “(mathematics) an expression such that each term is generated by repeating a particular mathematical operation”, according to the WordNet. Recursion is one of the most powerful “tools” in a functional programming language and so it is for Erlang. Recursion can be used to apply divide and conquer techniques to problem solving, where a problem is broken to smaller subproblems, the subproblems are solved, and the results are “merged” to generate the final result.

Recursion happens when a function’s body definition includes a call to the function itself.

functionA(...) ->
    Body_before_recursion, % optional
    functionA(...),
    Body_after_recursion. % optional

Recursion is used instead of the conventional loop statements of other programming languages, such as while and for in C.
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