My Thought about Camera & Lenses

A camera lens  (also known as photographic lens or photographic objective) is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically.

There is no major difference in principle between a lens used for a still camera, a video camera, A Telescope, a Microscope, or other apparatus, but the details of design and construction is different. A lens might be permanently fixed to a camera, or it might be interchangeable with lenses of different, Focal length, Aperture  and other properties.