Tham khảo tài liệu 'ajax for dumies phần 2', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 12 Part I Getting Started_ 3. The data that comes back from the server can be XML more on XML in Chapters 2 and 8 or just plain text if you prefer. The JavaScript code in the browser can read that data and put it to work immediately. That s how Ajax works it uses JavaScript in the browser and the XMLHttpRequest object to communicate with the server without page refreshes and handles the XML or other text data sent back from the server. In Chapter 3 I explain how all these components work together in more detail. This also points out what you ll need to develop Web pages with Ajax. You ll add JavaScript code to your Web page to fetch data from the server I cover JavaScript in Chapter 2 and you ll need to store data and possibly write server-side code to interact with the browser behind the scenes. In other words you re going to need access to an online server where you can store the data that you will fetch using Ajax. Besides just storing data on the server you might want to put code on the server that your JavaScript can interact with. For example a popular server-side language is PHP and many of the examples in this book show how you can connect to PHP scripts on Web servers by using Ajax. Chapter 10 is a PHP primer getting you up to speed on that language if you re interested. So you re going to need a Web server to store your data on and if you want to run server-side programs as well your server has to support server-side coding for the language you want to work with such as PHP . What Can You Do with Ajax The technology for Ajax has been around since 1998 and a handful of applications such as Microsoft s Outlook Web Access have already put it to use. But Ajax didn t really catch on until early 2005 when a couple of high-profile Web applications such as Google Suggest and Google Maps both reviewed later in this chapter put it to work and Jesse James Garrett wrote his article coining the term Ajax .
