Typology for video materials has been defined by classifying entries into three categories: art work, events and sources. The art work category is divided into different types: art video, documentary video, art film, experimental video, one-minute video, music video, video installation, interactive art, television art, fiction, animation, video performance, dance video, travel video, computer graphics, sound and hybrid art. These entries should include all areas of media art production. In discussing an individual art video, it should be taken into consideration that art works often include more than one type. The category of events is divided into workshops, discussions, festivals, concerts, performances (footage of performances which were not specifically edited or created by an artist, even though they feature an art work), lectures, presentations, exhibitions, screenings and seminars. Documents, articles, catalogues, interviews, essays and books are classified as sources.