Cold shoe

Most cameras have a hotshoe for attaching flashguns and other accessories. These are ‘hot’ because they have the electrical contacts needed to connect with and trigger the accessory that’s been added. A cold shoe is simply the same kind of mounting plate but without the connections. For example, they’re used for attaching video lights (which need no connection to the camera) or microphones (which connect to the camera by cable or wirelessly) or simply as a holder for external flashguns fired remotely by the camera.