Comment by Koshkin

To those who might be under the impression that recursion is not all that useful in the practice of commercial software development (as opposed to a purely academic interest or as a method of solving logical puzzles) I would point out the fact that recursion is the only way to emulate iteration in functional languages and, as such, it finds extensive use in the C++ template language as well as XSLT - two most used pure functional programming languages today.