Perspective,
in context of vision and visual perception, is the way in which objects appear to the eye based on their spatial attributes, or their dimensions and the position of the eye relative to the objects. There are two main meanings of the term: linear perspective and aerial perspective.
http://en.wikipedia.org/wiki/Perspective_(visual)
On 3rd Person Third-person shooter (TPS) is a genre of 3D action games in which the player character is visible on-screen, and the gameplay consists primarily of shooting.
A "third person shooter" is a game structured around shooting, and in which the player can see the avatar on-screen ("third person")
http://en.wikipedia.org/wiki/Third-person_shooterGame Camera SystemA virtual camera system aims at controlling a camera or a set of cameras in order to display a view of a 3D virtual world. Camera systems are used in videogames where their purpose is to show the action under the best possible angle; more generally, they are also used in 3D virtual worlds when a third person view is required. As opposed to film makers, virtual camera system creators have to deal with a world that is interactive and unpredictable. It is not possible to know where the player's character is going to be in the next few seconds; therefore it is not possible to plan the shots as film maker would do. In order to solve this issue, the system relies on certain rules or artificial intelligence to select the most appropriate shots.
http://en.wikipedia.org/wiki/Third_person_(video_games)#Third_person_view_games