Asynchronous JavaScript and XML (AJAX)

What is AJAX? This article will answer that question, as well as, define some other pertinent technical terms. Why is AJAX important? The discussion will cover what makes AJAX significant with regard to the internet and the ways in which AJAX is important from a business standpoint. It will conclude with some thoughts about competition in the sector.

AJAX is a tool used by web developers to create Rich Internet Applications (RIA), which are applications that have a user interface similar to desktop applications. This tool makes use of several internet protocols and languages (JavaScript, XML, XMLHttpRequest, XLST) to provide the resulting RIA experience. JavaScript is the scripting language used in the development, but the use of XMLHttpRequest to make asynchronous requests for XML data is what makes this tool different. So, you may ask, what's the big deal?

What makes AJAX an important technology? The answer is twofold: A better user experience on the web and less bandwidth usage. Before AJAX, most web page requests from a user would retransmit the entire page. This process is somewhat cumbersome and the user doesn't have a smooth online experience. With AJAX, only the pertinent data is requested and returned, leaving the web page relatively unchanged. How is this similar to desktop operation? Well, imagine what it would be like if Microsoft Word reloaded the entire document every time a change was made. Users today, more than ever, demand seamless and time-saving applications.

Another key benefit of AJAX is the savings on bandwidth. Data traffic on the internet increases daily and any method for reducing traffic is always welcome. Since this tool only transmits requested data, traffic is significantly reduced. Just think about those web pages that are very graphics intensive or contain multimedia. It doesn't take many full page transmissions to add up to lots of bandwidth wasted. How does all this translate into business?

Businesses make money by meeting customer needs. When it comes to web sites, presentation is a large part of that need. If users don't have a pleasant online experience, they may never return to a particular site. AJAX allows businesses to provide an interactive experience for their customers. Two examples of companies using AJAX are Google Maps and Goowy (see references for site). On Google, you have an interactive map experience without page reloads. Goowy acts as a web desktop manager by providing a means to use various tools such as mail, calendar, and contacts. As AJAX matures, more and more companies will be developing interactive sites because users will demand it. Why else should businesses use AJAX?

Another good reason to develop with AJAX has to do with dollars. In addition to the potential for new users, there are other ways in which a company can garner a significant return-on-investment (ROI) using this tool. As stated previously, AJAX saves bandwidth. According to Alexei White at Ajaxinfo.com, the ROI can be measured by calculating the difference in time per transaction using AJAX versus the page transmit method. His data reflects a 36 second difference per transaction. Using a conservative 50,000 transactions per year and $20 an hour labor rate, the savings come out to $10,000. As you can see, with companies that have millions of transactions per year, the savings can be significant. What about competing technologies? There are several technologies (such as XUL, Flex, SVG, XAML) being used to provide the RIA experience. These competing methods all have their advantages and disadvantages. What makes AJAX the choice to use by the majority of web developers? The most important reason is the fact it is open-standards based and can be used across different platforms and browsers. Another reason pertains to training. The learning curve is relatively small since most of the parts that make up AJAX have been used for many years. And finally, the competitors just aren't ready. While some of them may have superior qualities over AJAX, they aren't mature enough to gain widespread usage. For these reasons, AJAX was voted Technology of the Year for 2006 by developer.com.