HTML and Future Internet Explorer Compatibility with SharePoint
As new versions of Internet Explorer are released, the way HTML is rendered by the browser could change over time. To address the possibility of changes, Microsoft uses the X-UA-Compatible META tag that targets HTML markup to a specific version of Internet Explorer. The default SharePoint 2010 master pages are set to force current and future versions of Internet Explorer to render HTML in Internet Explorer 8 mode like the following markup:
<meta http-equiv="X-UA-Compatibile" content="IE=IE8" />
The Adventure Works Travel HTML includes the META tag to help ensure future Internet Explorer versions will display the SharePoint HTML properly.
For more information about the Internet Explorer Standards Mode, see META Tags and Locking in Future Compatibility.