A wipe involves one shot replacing another, traveling from one side of the frame to another. Think of a vertical line passing from the right side of the frame to the left. On the left side of this line, we have shot A, and on the right side of this line is shot B. When this line reaches the left edge of the frame, shot B will completely fill the scene, and the transition is complete. This example describes a vertical line wipe, though this is but one type of wipe.