Used to when you are working with a list of values that are related to each other
Use square brackets to create an array (this is also how you quickly recognize arrays)
Values in an array are separated by commas
We can store variables just like any other data type
You can create that doesn’t initially contain any values, this is called an empty array
An array can also be created with initial values
Square brackets are a means of identifying if a variable is an array
// declare a variable as an empty array
let numbers = [];
// or you can declare an array with initial values
let streets = ['Broadway', 'Houston', 'Grand'];
Values in an array are accessed as if they are in a numbered list
Arrays are zero based meaning the 1st “value” in an array is at position (index) 0, the 2nd element is at position 1, and so on
You access the value of an element in the array by passing the index of the item in square brackets
let streets = ['Broadway', 'Houston', 'Grand'];
// access the 2nd street listed in the array which is at index 1
let streetTwo = streets[1];
// declare a variable called chipmunks and use it to store
// an array of names
let chipmunks = ["Alvin", "Simon", "Theodore"];
// reference the first value in the array
// here we pass in a zero, since that represents the first
// element (value) in an array
let bandMember = chipmunks[0];
// the value stored in bandMember is "Alvin"
= (equal sign)
// declare a variable called newEditionMembers and use it to store
// an array of names
let newEditionMembers = ["Ricky Bell", "Michael Bivins", "Bobby Brown", "Ronnie DeVoe", "Ralph Tresvant"]
// We are going replace Bobby Brown with Johnny Gill
// by referencing the 3rd element of the array by using index 2
// and then use assignment (just an equal sign) to change
// the value to Johnny Gill
newEditionMembers[2] = "Johnny Gill";
Arrays are a flexible and powerful feature of Javascript (and other programming languages as well). Click here for more information about Arrays