Brainfuck is an amusing and minimalistic programming language which doesn't serve any real purpose except being a funny joke, challenging programmers and testing the boundaries of computer language design.

Warning! Brainfuck isn't suitable for practical use when programming!

Wikipedia has more information about the Brainfuck language.

This is a piece of Ed-like source code in Brainfuck language, by Nicolas Favre-Felix:


The following was offered by Andrea Bolognani, with this comment:

The above version reads from standard input until it encounters a EOF character, and then starts printing ? in an infinite loop. I've written a drop-in replacement [...]; as an added bonus, this version uses only 69 instructions, which is 30 less than the one above.