Three components of a simple GUI
GUI structure
What is a frame?
Outer structure (contains everything else in GUI) - invisible to user
GUI structure
What is a panel?
Inner structure (contains everything else in GUI) - invisible to user
Purpose of a GUI
Provides user with an interface to the application (client-side)
Invokes callback methods in response to events from user
Aims to provide intuitive use of system for a normal user