Answers:         These files are simply zipped file using java jar tool. These files are created for different purposes. Here is the description of these files: .jar files: These files are with the .jar extension. The .jar files contain the libraries, resources and accessories files like property files. .War files: These files are with the .war extension. The war file contains the web application that can be deployed on the any servlet/jsp container. The .war file contains jsp, html, JavaScript and other files for necessary for the development of web applications. .ear files: The .ear file contains the EJB modules of the application.