General info :
In North American television, a TV series is a connected set of television program episodes that run under the same title, possibly spanning many seasons. During the 1950s, it was common for television seasons to consist of more than 30 episodes—however, the average length has been declining since. Until the 1980s, most new programs for the US broadcast networks debuted in the "fall season", which ran from September through March and nominally contained 24 to 26 episodes. Since at least the 2000s, new broadcast television series are often ordered (funded) for just the first 10 to 13 episodes, to gauge audience interest. If a series is popular, the network places a "back nine order" and the season is completed to the regular 20 to 26 episodes. While network orders for 13- or 22-episode seasons are still pervasive in the television industry, several shows have deviated from this traditional trend such as miniseries, short, closed-ended series, typically six or more hours in two or more parts (nights), similar to an extended television movie. The episode runtime of television shows produced for streaming platforms, such as Netflix and Hulu, can vary from just under 30 minutes to over one hour long. Internet-based series with episode runtimes of less than 25 minutes are considered web series.
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