A camera flash is a device that produces a brief burst of bright light to illuminate a scene when taking a photograph. It helps to brighten subjects in low-light conditions, reducing shadows and enhancing details. The flash can be built into the camera or used as an external accessory. When the shutter button is pressed, the flash fires, synchronizing with the camera's shutter to capture the moment. Different types of flashes, such as speedlights and studio strobes, offer various features and power levels, allowing photographers to achieve desired lighting effects in their images.