JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE HTML>
<html lang="en-US">
<head>
    <meta charset="UTF-8">
    <title>Learning About Backbone.js Collection</title>
</head>
<body>

<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<script type="text/javascript" src="http://documentcloud.github.com/underscore/underscore-min.js"></script>
<script type="text/javascript" src="http://documentcloud.github.com/backbone/backbone-min.js"></script>
</body>
</html>

JavaScript

var Person = Backbone.Model.extend({
 initialize: function() {
  console.log('Person is initialized.');
 },
 defaults: {
  name: 'undefined',
  age: 'undefined'
 }
});
 
var People = Backbone.Collection.extend({
 initialize: function() {
  console.log("People Collection is initialized");
 },
 model: Person
});
 
var person = new Person({name:"Joe"});
 
var people = new People(person);
people.add([{name:"Bob"}, {name:"Jim"}]);
 
console.log(people.toJSON());