An external flash is a portable lighting device used in photography to enhance illumination. Unlike built-in camera flashes, external flashes can be mounted on the camera or used off-camera, providing greater flexibility in lighting angles and intensity. They are especially useful in low-light conditions or when capturing subjects with backlighting. These flashes often come with adjustable settings, allowing photographers to control the brightness and direction of the light. Many external flashes are compatible with various camera brands, such as Canon and Nikon, and can be used for different photography styles, including portrait and event photography.