In the last few years everybody has started talking about functional programming. On one end we have “mainstream languages” adopting “functional style” and on the other we have the ivory tower-like Haskell and it’s passionate community. It’s seems that functional programming is here to stay. This talk will explain what it’s all about, how it looks like in different languages and what we can learn from it. It’ll show a bunch of weird code, a few strange languages and a couple of take-aways you can apply everywhere – even in C.