//There are 3 types of Collections in Javascript:
//-Indexed Collections
//-Keyed Collections
//-DOM Collections

// Elements are based on index values - in JavaScript starting from 0.
var indexed = []         
// Elements are based on key-value pairs 
var keyed = {}         
// HTML elements, based on index values, starting from 0.
let DomCollection = document.getElementsByTagName("p");