If you write JavaScript, you have probably used higher-order functions and not even noticed. If you have ever replaced a for loop with an array method, you’ve used higher-order functions.

In the past two columns, we’ve looked at higher-order functions and talked a little bit about the power of functional programming. So far, the concepts we’ve covered do little to indicate how ...

Learn what the "this" keyword does in JavaScript in 100 seconds. And stay tuned for a few minutes of more advanced discussion after the credits.