Human–Computer Interaction

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Human–ComPuter InteraCtIon

directed to the target program or process), to invoke its corresponding

handler.

Note that an event does not necessarily correspond exactly just to

an individual physical input. e stream of raw inputs may be filtered

and processed to form/find meaningful input sequences from the cur-

rent context. For instance, a sequence of raw inputs may form a mean-

ingful event such as a double-click command, keyboard commands

with modifiers (e.g., --), and mouse enter/exit commands

(e.g., detection of mouse cursor leaving a particular window).

Figure 5.5 shows the two-tier event-queuing system in greater

detail. ere is ...