3.1. Adding a Touch of Ajax

The term Ajax has become such a buzzword that I’m not even sure I know what it means anymore. For the purposes of this book, I’m going to use Ajax to refer to the technique of using JavaScript to send requests to a web server without reloading the current page (e.g., to retrieve some HTML, submit a form, and so on). This approach makes for a very smooth user experience, but does require that you reinvent a lot of wheels.

For example, if you are loading external pages dynamically, the browser will not give any indication of progress or errors to the users. Furthermore, the back button will not work as expected unless you take pains to support it. In other words, you have to do a lot of work to make a sweet Ajax app. Even so, there are some very good reasons to go to the trouble. In particular, it opens the door to creating iPhone apps that can run full-screen (Section 3.6) and even offline (Chapter 6).