Object - Data Type

An array is a special type of object and is a reference data type.
Arrays should be used when you have ordered data.

let people = ["steve"] 
let array2 = people 
alert ( people ==== array2 )    // two variable references 
people.push ("john") 
alert ( array2 )    // "steve","john" 

var people = []; 
people[0] = "steve"; 
people[1] = "john"; 
people[2] = "david"; 

This is the array literal

var people = ["steve", "john", "david"]; 

This uses the keyword Array

var people = new Array("steve", "john", "david"); 

Trailing Comma

Arrays can include a trailing comma

var people = [ 
   "steve", 
   "john", 
   "david", 
];