If you use builder tools, such as Delphi or Visual Basic, you are already familiar with the notion of a bean. A JavaBean is a reusable software component that is written in Java programming language. It can be visually manipulated in builder tools. A JavaBean is often referred to simply as a Bean.
Software components are self-contained, reusable software units.
Using visual application builder tools, software components can be composed into applets, applications, servlets, and composite components. You perform this composition within a graphical user interface, and you can immediately see the results of your work. Reusable Software Components Reusable software components apply the concept of interchangeable parts to the field of software construction. Other industries have long profited from reusable components. For example, the builder tool above shows a calculator component that is built from 16 button components, a text field component, and a panel with buttons and a text display.