+F-number, or f-stop, quantifies a lens's [aperture](/wiki/Aperture) opening relative to its focal length. A smaller f-number denotes a wider opening, allowing more light for brighter [exposure](/wiki/Exposure) and a shallower depth of field. It's a fundamental control in photography, shaping the visual outcome of an image.
+## See also
+- [Depth of Field](/wiki/Depth_of_Field)
+- [Shutter Speed](/wiki/Shutter_Speed)
+- [ISO](/wiki/ISO)