Big Thinkers is a former ZDTV television program. It featured a half-hour interview with a "big thinker" in science, technology, and other fields. The show was originally hosted by Mark Eddo, later replaced by John C. Dvorak. In 2001 the show changed its format, transforming from a weekly half-hour interview to a documentary-style program. This new format was initially referred to on the TechTV website as Big Thinkers 2.0. The new incarnation of the Big Thinkers series was produced by Winton / duPont Films, a documentary film company located in the Presidio of San Francisco. Interviews were filmed in a 16:9 format and intercut with public domain material from the Prelinger Archives. This archival footage was used to create visual metaphors highlighting the speaker's points.