Arrays
Learn how to use arrays in JavaScript

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An array is a collection of elements.

We can initialize an empty array in these 2 different ways:

const a = []

The first is using the array literal syntax.

You can pre-fill the array using this syntax:

const a = [1, 2, 3]

An array can hold any value, even value of different types, like numbers and strings or even other arrays:

const a = [1, 'Flavio', ['a', 'b']]

You can access any element of the array by referencing its index. The first item has index zero:

const a = [1, 2, 3]

a[0] //1
a[1] //2
a[2] //3

Lessons in this unit:

0: ▶︎ Introduction
1: Number of items in an array
2: Create a new array from an existing array
3: Adding an item to an existing array
4: Adding at the beginning of an array
5: Adding multiple items to the array
6: Removing an item from an array
7: Modifying an existing array without mutating it
8: Arrays of arrays
9: Filling an array
10: Array destructuring
11: Check if an array contains a specific value
12: Array Recipes