The advent of photography, from the Ancient Greek words φως phos ("light"), and γραφη graphê ("stylus", "paintbrush") or γραφω graphō (the verb, "I write/draw"), together meaning "drawing with light" or "representation by means of lines" or "drawing", has gained the interest of scientists and artists from its inception. Scientists have used photography to record and study movements, such as Eadweard Muybridge's study of human and animal locomotion (1887). Artists are equally interested in these aspects but also try to explore avenues other than the photo-mechanical representation of reality, such as the pictorialist movement. Military, police and security forces use photography for surveillance, recognition and data storage. Photography is used to preserve favorite memories and as a source of entertainment.
The first successful permanent photograph was produced by Niépce. He began experimenting with processes to set optical images in 1793. Some of his early experiments produced images, but they faded rapidly. He was said to have first produced long lasting images in 1824.
The first real zoom lens, which retained near-sharp focus while the effective focal length of the lens assembly was changed, was patented in 1902 by Clile. C. Allen (U.S. Patent 696,788). The first industrial production was the Bell and Howell Cooke "Varo" 40-120mm Lens for 35mm movie cameras introduced in 1932. The Kilfitt 36-82mm/2.8 Zoomar introduced in 1959 was the first zoom lens in regular production for still 35mm photography.
Since then, advances in optical design, particularly the use of computers for optical ray tracing, has made the design and construction of zoom lenses much easier, and they are now used widely in professional and amateur photography.