A good answer might be:

I asked for button objects that do what I want. Somebody else did all the real work. The buttons are components that can be added with minimum effort.

In Java programming, you can get the GUI components you want merely by asking for them. Most of the work has already been done and is contained in the Abstract Windowing Toolkit (AWT), a package that contains classes for graphics and GUI programming. To use the AWT in a program you will need to import it:

import java.awt.*;

Now you can use the AWT to create windows, frames, buttons, menus and other components.

A user interacting with a GUI application generates events, which the application must handle, in what ever order they arrive. The picture shows this. Each time the user does something, an event is sent to the application. Different events are sent to different parts of the application. The application has to work correctly no matter what the user does.

A GUI program consists of three types of software:

1. Components that make up the Graphical User Interface.
2. Listeners that receive the events and respond to them.
3. Application code that does useful work for the user.

In writing a GUI application you do these three tasks separately (while keeping the big picture in mind.) In really big software projects there will be an entire team of programmers devoted to each of the three tasks. We will start smaller.

QUESTION 3:

Consider an AM radio and its user interface. Match each part of the radio with its analogous part in a GUI application.