The complete guide to JavaScript arrays

Arrays are a very useful part of JavaScript, and come in handy for things from text manipulation to image processing!

Whether you’re a complete beginner or coming for some more advanced array functions, this article is for you!

The contents of this article:

First of all, sorry for another clickbait-y title. However, I promise that this is a complete guide! In fact, so complete that it needs a table of contents! I never thought I’d have to do this, but here we go…

• What is an array?
• How to reference a value in an array
• Array functions
  • string.split()
  • array.join()
  • array.reverse()
  • array.indexOf()
  • array.lastIndexOf()
  • array.includes()
  • array.find()
  • array.findIndex()
  • array.map()
  • array.filter()
  • array.reduce()
  • array.sort()
  • array.splice()
• Nested arrays

I know that some of you may already know the basics of arrays, in which case feel free to go to whichever of those sections you don’t know already. Otherwise, start from the beginning and enjoy the ride!

Note that if you’re a complete beginner to arrays, you might want to only read part of this article for the moment. Or, depending on your learning style, you might want to read the whole thing! If you’re going to only read part of it, I recommend that you stop after How to reference a value in an array or array.includes(). But don’t forget to scroll down for the conclusion!

Let’s get started already!