a.The big close-up fills the frame with a face.

b. The close-up includes the head and shoulders.

c. The medium shot includes most of the body.

d. The long shot consists of the whole body and its surroundings.

These categories are not exact, but provide clues for classifying shots. To establish a location and explain a situation, traditionally a movement from long shot to medium shot to close-up is used. Conversely, in a movement from big close-up to long shot (as in images a-d above), you expect to see action happening on a larger scale. For example, the man might now interact with the old woman; or a leave-taking from the action might now take place (as could happen at the end of a sequence.)

more examples