his book, "Tube of Plenty: The Evolution of American Television", with replay technology, "brutal collisions became ballets, and end runs and forward passes became miracles of human coordination". Thanks in large part to instant replay, televised football became evening entertainment, perfected by ABC-TV's Monday Night Football, and enjoyed by a wide audience. Marshall McLuhan, the noted communication theorist, famously said that any new medium contains all prior media within it. McLuhan gave Tony Verna's invention of instant replay as a good example. "Until the advent of the instant replay, televised football had served simply as a substitute for physically attending the game; the advent of instant replay – which is possible only with the television – marks a post-convergent moment in the medium of television". In sports production for television During the live television transmission of sports events, instant replay is often used to show again a passage of play which was especially important or remarkable, or which was unclear at first viewing. Replays are typically shown during a break or lull in the action; in modern broadcasts, it will be at the next break in play, although older systems were sometimes less instant. The replay may be in slow motion or feature shots from multiple camera angles. Video servers, with their advanced technology, have allowed for more complex replays, such as freeze frame, frame-by-frame review, replay at variable speeds, overlaying of virtual graphics, instant analysis tools such as ball speed or immediate distance calculation. Sports commentators analyze the replay footage when it is being played, rather than describing the concurrent live action. Instant replays are used today in broadcasting extreme sports, where the speed of the action is too high to be easily interpreted by the naked eye, using combinations of advanced technologies such as video servers and high-speed cameras recording at up to several thousand frames per second. Sports production facilities often dedicate one or more cameras to cover star players, or a key player likely to make a big play in a specific context (e.g. on last down and long in North American football, production crews will often isolate a wide receiver with sure hands in a crowd and/or superior foot speed). These are sometimes called isolation cameras, isolated cameras, or iso-cams for short. Production equipment EVS Broadcast Equipment is a leading manufacturer of replay production servers which have been used by major broadcasters for large events