Sams Teach Yourself JavaScript™ in 24 Hours, Fifth Edition

Hour 16. Introducing Ajax

What You’ll Learn in This Hour

• The anatomy of an Ajax application

• About the components of an Ajax application

• What the XMLHttpRequest object does

• Sending messages to the server

• Dealing with the server response

JavaScript is a client-side scripting language, and all of the examples you’ve used so far have been limited entirely to client-side coding. Ajax (also known as remote scripting) allows you to access server-side programs and use their capabilities in your client-side scripts.

Here in Part IV, “Ajax,” you learn how to create and deploy Ajax applications.

The Anatomy of Ajax

So far we’ve discussed only the traditional page-based model of a website user interface.

When you interact with such a website, ...