Event

In computer programming, event-driven programming is a programming paradigm in which the flow of the program is determined by external events. Typical event can be UI events from mice, keyboards, touchpads and touchscreens, or external sensor inputs, or be programmatically generated (message passing) from other programs or threads, or network events.
Event-driven programming is the dominant paradigm used in graphical user interfaces applications and network servers.
In an event-driven application, there is generally an event loop that listens for events... plus