The content owner controls the price that is charged, and Google takes a cut from every video sold.
Any content can be made available, from TV series to home videos and footage shot at conferences.
Google co-founder Larry Page expects the service to enable a market for digital video downloads while offering content producers a new way to monetise their video.
"People are really concerned about the TiVo issue," he said. "We would like the broadest [offering of] video to be available so that this service can be successful."
Users are required to download a specially designed Google video player which uses a proprietary digital rights management technology.
The service launches with a library of 3,000 videos available for download. Content partners include CBS, owner of television series including Star Trek and Crime Scene Investigation, and the National Basketball Association. Downloads of CBS television series will be available at $1.99 per episode.
Google will not allow the sale of 'adult' videos, although chief executive Eric Schmidt said in a meeting with media after Page's keynote that the company had considered this option. Google has chosen instead to focus on the green-field market of regular video downloads.
"The [pornography market] is already well served," said Schmidt, referring to the broad availability of adult video downloads. "There was no need to take our resources and work on that problem. The problem of non-pornography turned out to be non-served."
The company will monitor all submitted videos and will remove any that violate its terms and conditions.
Google also launched a new service dubbed Google Pack, which bundles several applications including a six-month trial version of Norton Antivirus 2005, Firefox, Acrobat Reader 7, an anti-spyware suite and several Google products like Google Talk, Google Earth and Picasa.
The company created the free bundle in a response to the problems encountered by one of the company's founders when he installed a new computer for a family member.
The bundle consists of a single download that will automatically fetch additional packages as well as updates. New applications can be added to the suite at a later stage.
Google Pack is available for download here.
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