motion picture made and distributed outside the commercial film industry, usually as an artistic expression of its maker, who often acts as its producer, director, writer, photographer, and editor. Underground films usually display greater freedom in form, technique, and content than films directed toward a mass audience and distributed through regular commercial outlets. The term underground film came into common use in the 1950s, when the greater availability of good-quality 16-millimetre film stock and equipment permitted an increasing number of nonprofessionals to engage in cinema art. The term was also applied to earlier films that were considered too experimental, too frank, or too esoteric for the general public, made both by professionals and by amateurs.
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