In relation to US film production, what is a gaffer?
On film and television crews, the gaffer, or chief lighting technician, is the head electrician. Gaffers are responsible for coming up with a plan to light every scene in your movie or TV show. They have to know every detail about the production and work in concert with the cinematographer and director to help achieve a consistent look and feel.
Hollywood gaffers are part of the IATSE, International Alliance of Theatrical Stage Employees, Local 728 Studio Electrical Lighting Technicians Union.
The term "gaffer" hasn't always been tied to the film industry. Etymologically, the word, meaning "elderly rustic", dates back to the 1580s and was used as a contraction of "godfather". Later on in history, "gaffer" extended to refer not only to "old men" but foremen and supervisors.
Additionally, the term "gaff" dates back even further to the 1300s and was originally used to refer to an "iron hook" used for rigging boats.
"Gaffer" eventually made its way into the film industry to refer to the moving of overhead equipment to control lighting levels using a gaff, then, finally, to the "electrician in charge of lighting on a film set."