Presentation Zen: Making presentations in the TED style
TED has earned a lot of attention over the years for many reasons, including the nature and quality of its short-form conference presentations. All presenters lucky enough to be asked to speak at TED are given 18-minute slots maximum (some are for even less time such as 3- and 6-minute slots). Some who present at TED are not used to speaking on a large stage, or are at least not used to speaking on their topic with strict time restraints. TED does not make a big deal publicly out of the TED Commandments, but many TED presenters have referenced the speaking guidelines in their talks and in their blogs over the years (e.g., Ben Saunders).
Source: www.presentationzen.com