When you define and execute a function in JavaScript and Node, the variables that exist around it are available to the function. This simple idea, known as a closure, gives us some serious power.

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.

At Microsoft's Ignite 2017 conference today, the company announced a range of new features that will be coming to its Excel application, such as JavaScript Custom Functions and more.