Modules are packaged based on their functionality as EAR, JAR and WAR files.
JAR files (.jar) : Modules which contain EJB class files and EJB deployment descriptor are packed as JAR files.
WAR Files (.war) : Web modules which contain Servlet class files, JSP Files, supporting files, GIF and HTML files are packaged as JAR file.
EAR Files (.ear) : ‘.jar’ & ‘.war’ files are packaged as JAR files. ‘Ear’ stands for enterprise archive. These files are deployed in the application server.
