<P> In computing, an event is an action or occurrence recognized by software, often originating asynchronously from the external environment, that may be handled by the software . Computer events can be generated or triggered by the system, by the user or in other ways . Typically, events are handled synchronously with the program flow, that is, the software may have one or more dedicated places where events are handled, frequently an event loop . A source of events includes the user, who may interact with the software by way of, for example, keystrokes on the keyboard . Another source is a hardware device such as a timer . Software can also trigger its own set of events into the event loop, e.g. to communicate the completion of a task . Software that changes its behavior in response to events is said to be event - driven, often with the goal of being interactive . </P> <P> Event driven systems are typically used when there is some asynchronous external activity that needs to be handled by a program; for example, a user who presses a button on his mouse . An event driven system typically runs an event loop, that keeps waiting for such activities, e.g. input from devices or internal alarms . When one of these occurs, it collects data about the event and dispatches the event to the event handler software that will deal with it . </P>

Discuss how windows 8 operating system can be viewed as an event driven application