A good answer might be:

Click!

Event-driven Programming

When you perform an action on a graphical component you generate an event. In event-driven programming the program responds to events. The program responds to events that the user generates in interacting with GUI components. The order of events is controlled by the user.

For example, you can generate an event by clicking on this button:     Or you could click on this button:    Click on the buttons a few more times in any order. The program (your Web browser, in this case) responds to whatever events you generate.

If your browser is written in Java, then Swing components generate the events and Java methods respond to them. If your browser is written in C++, then other components and methods, similar to Swing, are being used. (Most browsers are written in C++).

QUESTION 4:

How do you imagine that I wrote this Web page: