A JavaBeans tutorial is provided with the BDK that outlines many of the basic concepts associated with JavaBeans and the BeanBox test container. The JavaBeans specification by Sun Microsystems defines them as "reusable software components that can be manipulated visually in a builder tool".
In spite of many similarities, JavaBeans should not be confused with Enterprise JavaBeans (EJB), a server-side component technology that is part of Java EE.

JavaBeans makes it easy to reuse software components. Developers can use software components written by others without having to understand their inner workings.
To understand why software components are useful, think of a worker assembling a car. Instead of building a radio from scratch, for example, she simply obtains a radio and hooks it up with the rest of the car.