TheIn [[computer science]], the '''recursive functions''' are a class of [[function]]s from [[natural number]]s to [[natural number]]s which are "computable" in some intuitive sense. In fact, in [[computability theory]] it is shown that the recursive functions are precisely the functions that can be computed by [[Turing machine]]s. Recursive functions are related to [[primitive recursive function|primitive recursive functions]], and their inductive definition (below) builds upon that of the primitive recursive functions.
Not every recursive function is primitive recursive as well - the most famous example is the [[Ackermann function]].