Compressed package containing Java-based Web components and applications that are run on a Web server; formatted the same way as a .JAR file, but includes additional information that tells the application server which Java servlet class to run. WAR files may contain server-side utility classes (such as database beans and shopping carts), static Web resources (HTML, image, and sound files), and client-side classes (applets and utility classes). They can be run on a Web server using a supporting program such as the Tomcat Web Application Manager within Apache. Since WAR files are saved in an archive format, the contents of a WAR file can be extracted using a file decompression utility like Stuffit Expander.