Portal may refer to:

A film, also called a movie or motion picture, is a series of still or moving images. It is produced by recording photographic images with cameras, or by creating images using animation techniques or visual effects. The process of filmmaking has developed into an art form and industry.

Films are cultural artifacts created by specific cultures, which reflect those cultures, and, in turn, affect them. Film is considered to be an important art form, a source of popular entertainment and a powerful method for educating – or indoctrinating – citizens. The visual elements of cinema give motion pictures a universal power of communication. Some films have become popular worldwide attractions by using dubbing or subtitles that translate the dialogue into the language of the viewer.

Films are made up of a series of individual images called frames. When these images are shown rapidly in succession, a viewer has the illusion that motion is occurring. The viewer cannot see the flickering between frames due to an effect known as persistence of vision, whereby the eye retains a visual image for a fraction of a second after the source has been removed. Viewers perceive motion due to a psychological effect called beta movement.

Dan Trachtenberg is a filmmaker and video podcast host from the Philadelphia suburbs who currently resides in the Los Angeles metro area. He is one of the three hosts of The Totally Rad Show and a former co-host of Geekdrome. Both programs are hosted at Revision3. In addition to working on Internet shows, Trachtenberg is the writer/director of the 2003 short film Kickin' and the director of various television commercials and public service announcements.

Trachtenberg has directed commercials for Lexus, Nike, and Coca Cola. In April, 2008, he joined Tight Films, for which he collaborated with Matt Wolf on an alternate reality game for Hellboy II: The Golden Army."

He directed the internet show, "Ctrl+Alt+Chicken."

On August 23, 2011, Trachtenberg released the short film, Portal: No Escape. Based on the video game, Portal, the film drew more than one million views within its first day on YouTube.^{[citation needed]} Within two months, the number of viewers surpassed six million.^{[citation needed]}

Tahmoh Penikett (pronounced [ˈtaʔmo] /ˈpɛnɨkɨt/; born May 20, 1975) is a Canadian actor. He is best known for his roles as Karl "Helo" Agathon on the Sci Fi Channel's television series Battlestar Galactica and as Paul Ballard in Joss Whedon's Dollhouse'.

Penikett is the son of former Yukon premier Tony Penikett, who immigrated to Victoria, British Columbia from England at age 12, and Lulla Sierra Johns, of the White River First Nation in the Yukon. He has two siblings, twin sisters Sarah and Stephanie. He graduated from the Victoria Motion Picture School and studied at the Lyric School of Acting in Vancouver.

Penikett currently lives in Vancouver with his family.

In support of the Babz Chula Lifeline for Artists Society, which is raising money for their friend and fellow Canadian actor Chula's cancer treatment, Penikett and his Battlestar Galactica colleague Kandyse McClure auctioned off the opportunity to have dinner with both of them in Vancouver in April 2008.

He trains in muay thai and has showcased his ability in various roles, including in Battlestar Galactica and most notably as Agent Ballard in the fight sequences in Dollhouse, where he choreographed most of his own moves.