What is a "Grip"?

In the film industry a "Grip" is the name of the occupation for the person who is a lighting and rigging technician. They are part of their own department on the set of the film and are directed by the head of the department the "key grip". The Grip has two main roles whilst on set. The first is to work with the camera department to provide stable support for the camera when in unusual positions for filming such as on a ladder or crane. They also work closely with the electrical department to help with the setup of lighting to produce the desired "shot". In Australia, Grips do not play such a big role in lighting. During production the grip is just making sure that the equipment is ready to be used and that the camera's and lights are in their correct position or are stable where they are. When helping with the camera work the Grip does whatever they can to make the camera movement as seamless as possible.

The Grip is also in charge of the maintenance of the equipment to make sure it is working and ready to go when it is needed. They collaborate closely with the lighting and camera departments.
There are no proper courses that specifically make you a grip. There are Rigging Courses that are handy to help you become a licensed rigger to ensure that you can legally do everything you can to help with the production of a film whether it is getting the camera into position of hanging lights for the production. Riggers need to have a high school diploma to enter into the course. Most of their skills are acquired through job experience the course that Riggers take can take up to 3-4 years. In more recent years the grip has become a basic electrical technician on the set. There are courses to help you become a licensed electrician to allow you to work on the set of a film such as an advanced diploma of electrical engineering, which last for 2 years full time.
The Grip needs to have equipment ready to go straight away. They will often have a tool belt which has such items as an adjustable wrench, gaffer tape, stanley knife, tape measure, a flashlight and a multi tool.
Notable examples
There are not too many famous "grips" in the movie industry. In the film "Avatar" the main grip work was working with the camera crew on the dolly and crane. The grips job in these circumstances was to make the movement of the camera as smooth as possible.
Changes to the role
The film industry is always changing with new technologies being introduced and new techniques of capturing images and lighting the set, that the grip has changed to more of a rigging and electrical technician role to use these techniques to capture the best shot that they can.

Grip helping the camera department.

Other info from school workbook.