Errors. They happen. Sometimes we wish they wouldn't but they do and the code we write and the systems we build have to handle that. The processes by which we detect failures and handle them varies a lot though and the "right" way to deal with failures has been a topic of discussion generally only eclipsed by how to do packaging and how to format code.

Different languages, platforms, and frameworks all not only handle errors differently but frequently have entirely different ways of thinking about what an error even is. I'd like to take you on a bit of a philosophical exploration about what happens when things go wrong, how we know they've gone wrong, and what we do about it.