One of the aspects of Internet Explorer that evolved with the introduction of IE 8 Beta 1 is related to AJAX navigation. This is because of Microsoft's commitment to aligning IE with the latest versions of modern web standards. In this context, in its default standards rendering mode, IE8, even as early as Beta 1, a release dating back to March 5, 2008, concomitantly with the opening day of MIX08, delivers support for some portions of HTML5.

"One of the AJAX improvements we adopted in IE8 from HTML5 is AJAX page navigations. In IE8 mode, we provide support for script to update the travel log components (e.g. back/forward buttons, address bar) to reflect client-side updates to documents. This allows a better user experience where users can navigate back and forth without messing the AJAX application state," explained Sharath Udupa, Internet Explorer Developer.

According to Microsoft, the new AJAX navigation capabilities built into Internet Explorer 8 are designed to offer additional functionality to applications developed using asynchronous JavaScript and XML. What IE8 will effectively permit end users to do is to enjoy the browser's navigation buttons, including Back and Forward in order to move around inside AJAX programs, and not just from one web page to another. Michael S. Scherotter Developer Evangelist - Communications Sector of North America Microsoft, indicated that the Added AJAX navigation capabilities extend to support Silverlight as well.

"In IE8 mode, Internet Explorer treats window.location.hash updates like navigations and saves the previous document URL. The following actions occur as a result: the previous URL, which may be from the previous hash fragment, will be updated in the Address bar, Back button and other browser components; a 'click' sound will play as if a traditional navigation occurred; a new hashChanged event will fire," Scherotter added, providing examples here and here.

For additional info, you can access the Internet Explorer MIX08 Hands-on Labs here.