An instance of a class with its state stored as a serialized data stream.
JavaBeans use Java Object Serialization to enable beans to save their state and restore that state later. This enables the persistence of the bean's state.
You can find more information about Java Object Serialization at http://java.sun.com/products/javabeans/related.html.
You can learn more about bean persistence in the JavaBeans specification found at http://java.sun.com/products/javabeans/docs.