In Java Enterprise Edition (Java EE), a session bean is a type of enterprise bean that represents a session with a specific client. It is a server-side component that can be used to manage stateful interactions between a client and a server. There are two types of session beans: stateless session beans and stateful session beans.

A stateless session bean does not maintain any conversational state with the client, which means that it can handle requests from multiple clients simultaneously. It is typically used to perform simple, short-lived operations such as database queries or calculations.

A stateful session bean, on the other hand, maintains a conversational state with a specific client for the duration of the session. This means that it can store information about the client's interactions with the server and use this information to provide a personalized experience for the client. Stateful session beans are typically used for long-running business processes such as online shopping carts or banking transactions.

To create a session bean in Java EE, you typically create a Java class that implements the javax.ejb.SessionBean interface and annotate it with the @Stateless or @Stateful annotation, depending on the type of session bean you want to create. The SessionBean interface provides lifecycle methods that the container can use to manage the session bean, including ejbCreate(), ejbRemove(), and ejbPassivate().

Once you have created a session bean, you can use it in your web application by injecting it into a servlet or JSP page using the @EJB annotation. The container will handle the creation and management of the session bean, allowing you to focus on the business logic of your application.

Overall, session beans provide a powerful and flexible way to manage stateful interactions between a client and a server in a Java EE application. Whether you need to perform simple database queries or complex business processes, session beans can help you build scalable and maintainable enterprise applications.