Tracking Shot:

A tracking shot is when the camera moves forward and backward to focus upon a particular object or character. The shot is often called a tracking shot due to the fact that the camera is run along a small track in order to follow the action.
Sometimes it is called a dolly shot, due to the fact that a tripod on wheels is called a dolly and this is usually used for these types of shots in order to focus on objects and characters aswell as having the background in the view of the shot.