The document discusses various ways that Silverlight applications can connect to resources outside of the application using HTTP requests, web services, sockets and more. It covers reaching out to browsers, machines, the web and across domains or schemes. Key approaches include using classes like WebClient and HttpWebRequest to make HTTP requests, WCF for SOAP web services, ADO.NET for RESTful services, and sockets for asynchronous duplex communication. Policy files are also discussed for allowing cross-domain access.