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 ...

JavaScript variables hold a wide variety of information and can be used with virtually any data type. Here's how to use variables to store numbers, text strings, objects, and more.

JavaScript has a very powerful function system, where functions can be referenced just like any other variable. This is known as “first-class functions” and it’s a big source of JavaScript ...

After adding "y" to "x," JavaScript stores "11.234" in the "z" variable. You can control the number of decimal points that appear in a result by using the "toFixed" function. Instead of adding "x ...

This is a very unorthodox type of function, one that is impractical and only used here to demonstrate a potential use of global variables. It works, but it’s clumsy and more awkward to use.