Smith, The Attentional Theory of Cinematic Continuity

The Attentional Theory of Cinematic Continuity is an article by Tim J. Smith. It discusses the theories surrounding film editing and the techniques used to create a sense of continuity for the viewer. The cuts between discontinuous viewpoints that have been edited together into a single film can be quite jarring if special attention is not paid to the way the cuts are treated. The transition between separate shots can be smoothed with techniques such as visual cues, and the 180° rule.
The Hollywood Style
A scene filmed and edited in the Hollywood style commonly moves closer and closer to the subjects of the scene as time goes on. For example, the scene may begin with an establishing shot, which shows the setting and the spatial relationship between the characters. Then, the scene will cut to a a medium shot, which will show the characters from the waist up. If the scene contains a conversation between two characters, The Hollywood Style scene will often alternate between over the shoulder shots of both characters. Gradually, the scene will move from establishing shot to close up shots of the actor's faces. 
The 180-degree rules is almost always used, which means that the camera can never pass an imaginary line drawn through the middle of the scene, in order to allow the viewer to maintain an understanding of where the people and objects are in the scene. If the camera were to cross this line, the locations of objects would become flipped and this would be confusing to the continuity of the scene.
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