Presence is a theoretical concept describing the extent to which media represent the world (in both physical and social environments).[1] Presence is further described by Matthew Lombard and Theresa Ditton as “an illusion that a mediated experience is not mediated."[2] Today, it often considers the effect that people experience when they interact with a computer-mediated or computer-generated environment.[3] The conceptualization of presence borrows from multiple fields including communication, computer science, psychology, science, engineering, philosophy, and the arts. The concept of presence accounts for a variety of computer applications and Web-based entertainment today that are developed on the fundamentals of the phenomenon, in order to give people the sense of, as Sheridan called it, “being there."[4]
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was invoked but never defined (see the help page).