This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
This post explained it pretty well: http://www.coderanch.com/t/220150/Web-Services/java/Purpose-Web-Services-motivation-please Basically the difference is this: Web apps usually are delivered the user via a web browser of some sort, responding to user input and form posts. (Main presentation format: HTML) Web services are back end processes that occur behind the scenes, allowing business processes to communicate with each other in an open and platform neutral way. (Common Delivery mechanism: XML over HTTP)