An EJB JAR file is portable and can be used for different applications.
To assemble a Java EE application, package one or more modules (such as EJB JAR files) into an EAR file, the archive file that holds the application. When deploying the EAR file that contains the enterprise bean’s EJB JAR file, you also deploy the enterprise bean to the Enterprise Server. You can also deploy an EJB JAR that is not contained in an EAR file. Figure 14–2 shows the contents of an EJB JAR file.