Dolly Shot

A dolly is a cart which travels along tracks. The camera is mounted on the dolly and records the shot as it moves. Dolly shots have a number of applications and can provide very dramatic footage.

In many circles,
a dolly shot is also known as a tracking shot or trucking shot. However, some professionals prefer the more rigid terminology which defines dolly as the in-and-out movement (i.e. closer/further away from the subject), while tracking means side-to-side movement.
They're used by directors to establish other shots i.e. tracking shots of a location in the production.