Definition:
The Delegation Event model is one of the many techniques used to handle events in GUI (Graphical User Interface) programming languages. GUI represents a system where an user visually/graphically interacts with the system. Other interactive systems are text based or called CUI (Character User Interface). CUI interacts with the system by typing out commands in the console. GUI programming is inherently event driven; that means, whenever an user initiates an activity such as a mouse move that changes the co-ordinates of the mouse pointer in the screen, or clicks a button, scrolls a page, and so forth, each is deemed as an event that the GUI event handler maps the activity to a piece of code that explains what response the application should provide to the user.
Further Reading:
Book: Applying UML and Patterns by Craig Larman.
