I think we need to start describing configuration languages that describe how the thing is built and configured. - Joe Armstrong

I thought if you multiply two integers together, you get an integer. But apparently you don't in PHP. You get a floating point number, which gets bigger and bigger and that's okay. Until you get to factorial(171), and then you get "INF". I don't know what "INF" is. I think it's infinity actually. But in that case, it's probably wrong, because infinity is awfully big. Bigger than factorial(171).

Four languages to learn: C, Prolog, Erlang, Javascript.

The cornerstones of fault tolerant programming are to isolate errors to make sure if one thing crash it does not crash anything else. That's what the processes in operating system do.