In stagecraft, a c-clamp can refer to a number of different pieces of hardware, depending on its intended use.
Film and television grips commonly make use of c-clamps that are manufactured specifically for their industry.
These clamps are produced with integrated studs designed to accept the mounting hardware from a variety of small, lightweight lighting fixtures, allowing illumination to be placed in unusual or awkward locations quickly and easily.
C-clamps are commonly used in theatrical carpentry for the same purpose that non-theatrical carpenters employ them: for creating a quick, temporary, and non-destructive way of joining two objects together.
Legs are commonly attached to platforms via c-clamp before they are fastened together using a more permanent method (i.e. bolts).