Film is a sequence of moving images. It can be recorded on sensitive material, like celluloid, or digitally. The word comes from the thin layer of emulsion on a strip of plastic. That strip was the original medium of cinema. Today, film can refer to the medium, the art form, or the industry. A film is a movie. Film is cinema. The ambiguity is part of the word's history.

Celluloid film was the standard for over a century. It captured light on silver halide crystals, which were developed and projected. It had a distinct look, with grain, contrast, and color rendition that digital could not replicate. It was also fragile, flammable, and expensive. Digital cameras have largely replaced it, but some filmmakers still shoot on film. Christopher Nolan, Quentin Tarantino, and Wes Anderson are among the advocates. Kodak still produces film stock, and labs still process it.

Film is also an art form. It encompasses narrative, documentary, experimental, and animated works. It is a collaborative medium, involving writers, directors, actors, cinematographers, editors, composers, and hundreds of craftspeople. It is a commercial medium, driven by box office and streaming revenue. It is a cultural medium, reflecting and shaping the way we see the world. Film is many things at once. It is one of the defining art forms of the modern era.