An insert shot is a close-up of something that exists within the basic scene. The latter is typically visible within the establishing or wide shot. (Note close-up shot above from the scene on the left)..

Insert shots add needed information, information that wouldn't otherwise be immediately visible or clear.

In our earlier example of the new $100 bill, an ECU (extreme close-up) of the bill that was being discussed would be an insert shot.

Many years ago, the Russian filmmakers Pudovkin and Kuleshov conducted an experiment in which they juxtaposed various scenes with a shot of a man sitting motionless and totally expressionless in a chair.

The scenes included a close-up of a bowl of soup, a shot of a coffin containing a female corpse, and a shot of a little girl playing. To an audience viewing the edited film, the man suddenly became involved in these scenes.

When the shot of the man was placed next to the shot of the coffin, the audience thought that the actor showed deep sorrow. When it was placed next to the close-up of the food, the audience perceived hunger in his face; and when it was associated with the shot of the little girl, the audience saw the actor as experiencing parental pride.

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