Now you've seen a simple example of a JavaScript program 0:00 running outside the browser. 0:03 Let's go into a little more detail about what's available to you, and 0:05 what's not when writing applications like this. 0:08 As developers, we use the JavaScript programming language that's interpreted 0:12 and executed by the browser's engine against browser specific APIs 0:17 like the DOM, or document object model. 0:22 When thinking about a JavaScript program in the browser, 0:25 you can split it up into two distinct parts. 0:28 Firstly, native objects. 0:31 These are the objects provided by the JavaScript programming language, 0:33 objects like string, array, date, math, and many more. 0:37 You can use these in any environment, not just in the browser. 0:41 Secondly, host objects. 0:45 These are the objects provided by the environment. 0:47 In the case of the browser, it's things like Window, document, history, XMLHttpRequest, 0:50 HTTP request and many more. 0:55 As JavaScript became more in demand, 0:57 the performance of the JavaScript engines became more important. 0:59 JavaScript started becoming a more viable option 1:03 to build not just browser applications, but all types of applications. 1:06 Chrome, Google's Internet browser, began dominating the performance benchmarks. 1:10 With its JavaScript engine V8 going open source, it became 1:15 the perfect environment for something new to appear, something to write any type of 1:19 general purpose application in JavaScript and that was Node.js. 1:24 Ryan Dahl ripped Chrome's V8 JavaScript engine out of the browser 1:29 leaving all the browser host objects behind, and provided new ones to allow for 1:33 the new types of applications to be written. 1:37 Objects like HTTP, HTTPS, fs for file system, URL, OS and much more. 1:40 The coupling of the V8 engine with the APIs is known as the Node.js or 1:47 the Node.js environment. 1:53 JavaScript applications are now free to run stand alone on a personal computer or 1:55 even on the Internet running on a server. 2:00 The key to writing any JavaScript application 2:03 is knowing what's available to you. 2:06 The native object should be available to you no matter what the environment. 2:08 They're there both in the browser and in Node.js. 2:12 However, in each environment you'll have access to their particular host objects 2:16 which can be completely different. 2:20