The Technical crew, often abbreviated to "tech crew" or "techies", are the individuals employed behind the scenes (backstage) who control all the technical aspects of creating a concert, play, musical, opera or other live performance. The technical crew can be divided up into 13 or more crew members: Stage manager, Props, Back-Stage crew, Lighting Desk Operator, Followspot(s), Master Electrician, Deck Electrician, Sound Desk Operator, Sound Manager, Mic Manager, Stage Hand & Flymen. The role and composition of a tech crew can change significantly depending on the nature of an event, and often evolves as the production does. For example, in a simple theatre production, the technical crew might consist of a single person, operating the lights and controlling the volume of the sounds and music. In a large scale professional theatre productions, the technical crew can consist of dozens of different departments and may run into the hundreds of individuals.