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.
the .action suffix is a way of communicating with the Struts 2 interceptor that you want it to look for an action defined in the struts.xml file and execute a method on it. Without the suffix, the interceptor doesn't know if you're just trying to load an image file or HTML page, or display the contents of a directory.