The term "f-stop" refers to a measurement used in photography to indicate the size of the aperture opening in a camera lens. It is expressed as a fraction, such as f/2.8 or f/16, where a lower number means a larger opening that allows more light to enter the camera. This affects the exposure of the image and the depth of field, which is the range of distance that appears sharp in a photograph. Adjusting the f-stop can significantly influence the final image. A wider aperture (lower f-stop) creates a blurred background, emphasizing the subject, while a smaller aperture (higher f-stop) increases the sharpness of both the foreground and background. Understanding f-stops is essential for photographers to control light and achieve desired artistic effects in their work.