Definition:
The camera does not move on its own. Neither does most of the equipment that shapes how light falls on a scene. The grip department builds and operates the mechanical infrastructure that makes all of it possible: the dolly tracks, the camera cranes, the car mounts, and the flags and frames that control light without plugging into a wall.
What It Means in Movies:
Grips handle mechanics: anything that moves the camera or physically shapes and controls the light without generating it. A flag that cuts light from hitting the lens is a grip tool. The two departments work side by side on every setup, and the collaboration between them determines whether the shot is achievable.
Why It Matters:
Without the grip department, the camera stays still, and the lighting stays flat. Every sweeping crane shot, every smooth dolly move through a complex environment, every precisely shaped pool of light on a face: all of it depends on grip work that the audience never sees and never thinks about.
Example:
When a DP wants a long dolly track running the length of a corridor for a tracking shot, it is the grip department that lays the track, assembles the dolly, ensures the surface is level, and operates the move during the take. The camera operator rides the dolly. The dolly grip pushes it.