‘Higher-order functions’ is a fancy term for functions that take other functions as arguments or that return functions. Very powerful!

Learn how JavaScript’s built-in functions like map() and filter(), as well as compose() and chain(), support a more elegant handling of JavaScript arrays.

Peter looks at how to call a JavaScript function from your TypeScript code and do it in a type-safe way. Along the way, he dramatically simplifies a Backbone application by integrating Knockout.