MSDN Virtual Lab: A SharePoint Developer Introduction - Web Services - C# [ Source: Microsoft ]
January 2008- After completing this lab, you will be better able to use several SharePoint web services to expose data and manipulate SharePoint site configuration. While the SharePoint user interface is extremely configurable and flexible, it is often necessary to interact with SharePoint data and services at a much lower level. Access to information in SharePoint is provided by several mechanisms – Web services, SharePoint API & Object Model, RPC and more – each of which provides benefits and restrictions.