Nowadays JavaScript has three different keywords to declare a variable — var, let and, const. Each has its own properties and particularities. Let’s start by making a simple comparison table ...

Functions are self-contained routines that can be “called” elsewhere within your JavaScript code. Along with loops and conditionals, functions are an essential means of organizing software.

A function holds a set of actions that will run every time the function is called. This helps control the flow of our program and allows us to repeat a set of actions multiple times. Writing functions ...

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.