In film editing, transition refers to the way in which one shot is replaced by another. Several types of transitions have been utilised from the earliest years of cinema. Each type implores a different emotion.
The most commonly used type of transition is the cut. This type of transition is basically where a single shot is instantly replaced by another shot. Cuts are vital for the effects of juxtaposition. Although most cuts exist solely for a technical necessity, the abrupt replacement of one shot by the other often demands a certain interpretation from the viewer.
Transition: Fade In/Out
Fade outs occur when the picture is gradually substituted by a black screen or any other solid colour. Traditionally they have been used to conclude film productions.
Fade ins are merely the opposite; a solid colour gradually gives way to a picture, this has of course traditionally been used in the commencing of film productions.
Also known as overlapping, a dissolve happens when one shot is systematically replaced by the next. One disappears as the following appears. For a few seconds, they overlap, and both are visible. Commonly used to signify the passage of time.
Wipes are dynamic. They happen when one shot pushes the other off frame. George Lucas deliberately used them throughout the Star Wars series.
An old-fashioned transition hardly employed nowadays is the iris, when a circulars masking closes the picture to a black screen. In modern times, more sophisticated editing programs have introduced numerous other types of irises, like a star or heart. However, they have no purpose in serious filmmaking.