Enterprise JavaBeans, or EJBs, are a server-side component-based architecture that is used to build applications that are scalable, transactional, distributable, portable, and secure. If you think in terms of reusable code, then you will see why EJBs are so vital. EJBs are only concerned with the business logic of the application; the system logic is the requirement of the EJB container. EJB containers are basically application servers that provide you with a server platform to deploy your EJBs on.