Understanding scope in programming is key to appreciating how your variables interact with the rest of your code. In some languages, this can be quite straightforward, but JavaScript's anonymous functions and event handling features, along with a couple of little quirks, mean that handling scope in your applications can become frustrating.

This article discusses how JavaScript handles scope and how various JavaScript libraries provide methods for dealing with it and how they smooth out a few bumps. We'll also look at how you can get back to basics and do some interesting scope wrangling without a library, a useful approach if you're writing code that needs to stand alone.