TTL (Through The Lens) is a metering system used by cameras to measure the light that passes through the lens to determine the correct exposure settings. In flash photography, TTL allows the camera to measure the light reflected from the scene during a pre-flash and adjust the flash output for optimal exposure automatically. This ensures balanced and accurate lighting, even in complex or changing environments. TTL technology simplifies the photography process by automating exposure calculations, allowing photographers to focus more on composition and creativity. It is particularly beneficial in dynamic shooting situations, such as events or wildlife photography, where lighting conditions can change rapidly.