Silverlight Web Part
The Silverlight Web Part enables you to add compiled Silverlight applications (XAP files) to SharePoint pages without requiring any additional configuration. If you used SharePoint 2007 then it was also possible to deploy Silverlight applications to sites. However, doing so meant additional configuration to the Web front-end server and SharePoint Web application. In this section, you learn how to use the Silverlight Web Part to access and display XAP files.
By default, the out-of-the-box Silverlight Web Part has a time out of five seconds. If your XAP file is taking longer than five seconds to load then it displays an error message: Could not download the Silverlight application or the Silverlight Plugin did not load. ...