Photographic film which, when exposed and developed, forms a negative image of the subject on the film. This is then printed via an enlarger onto photographic paper - this is also developed and goes dark where light fell on it from the enlarger.
This is the most popular variety of photographic film, and is available in most film formats, being especially popular in APS and 35mm sizes; and speeds from 25 to 3200 ASA.
See also slide film.