AJAX 101, Part 2

Continued from Part 1 of this series, here are some of the major benefits of using AJAX:

• Improves a Web site User Interface, as an entire Web page doesn't have to be reloaded each time the user requests a change.
• Increases a Web page's interactivity, speed, and usability.

Some of the drawbacks of AJAX include:

• A browser's back button will not work consistently on AJAX sites. (Though there are workarounds for this.)
• Bookmarks are not able to save a changed AJAX state. (Again, there are workarounds.)
• Some latency may occur due to network response time.
• Search engines don't generally execute the JavaScript code required for AJAX, and as the AJAX states are not unique pages, search engines cannot spider them.
• As JavaScript is implemented differently on different browsers, there may be some incompatibility. This becomes a potentially big issue when Web sites try to support a broad base of Web browsers. Also, if users deactivate JavaScript support in their browser, the AJAX function will be disabled.

Other less ubiquitous alternatives to AJAX include XUL (a high-performance markup language only compatible with Mozilla browsers), XAML (Microsoft's next gen technology for creating rich user interfaces), and Java Applets (JAVA is available for multiple platforms).