<P> Sports broadcasts are carried through a number of televised media . Most of the major sports have some presence on commercial broadcast television, including all NFL regular season and most playoff games . National cable networks, beginning with ESPN in 1979 (along with its later sister channels that gradually launched beginning in the 1990s) and later joined by competitors such as NBCSN and Fox Sports 1, carry packages of assorted major professional and college sports . The vast majority of MLB, NHL and National Basketball Association (NBA) games are carried through regional sports networks, however the NFL only permits preseason games to air on RSNs on a limited basis (the league otherwise prohibits regular season and playoff games from airing on regional sports networks, but does permit national cable networks to acquire the rights to air them); the leagues (as well as the NFL) restrict the broadcast of their sports on regional networks to specific territories and require any person outside those territories to purchase an out - of - market sports package to watch the majority of their favored team's games . Regional sports networks can also provide outlets for minor league sports to broadcast their events . Unlike in some other countries, public television does not own any sports rights, nor has it ever been a major factor in sports television . </P> <P> While the majority of programs broadcast on American television are produced domestically, some programs carried in syndication, on public television or on cable are imported from other countries--most commonly, from the primarily English - speaking countries of Canada and the United Kingdom . PBS in particular, is commonly known for its broadcasts of British sitcoms (such as Monty Python's Flying Circus, Fawlty Towers, Keeping Up Appearances and Are You Being Served?), which typically air on its member stations on weekend evenings (although their scheduling is at the discretion of the station as these programs are primarily syndicated on the behalf of outside distributors); PBS was also responsible for bringing the hit period drama Downton Abbey to the U.S. and for initially popularizing the long - running science - fiction series Doctor Who in the country (the latter show now airs first - run episodes on BBC America, an outlet launched in 1998 that was specifically designed to bring BBC programming direct to the United States, although it continues to be syndicated to public television stations and is also syndicated to commercial digital multicast networks such as the Retro Television Network). </P> <P> Many of the programs imported from Canada are children's programs originally aired by channels such as YTV and Family Channel (such as Are You Afraid of the Dark?, Naturally, Sadie and Life with Derek). However, other Canadian series aimed at adults or more general audiences have also been syndicated in the United States; one network, Ion Life (a spin - off of Ion Television), has much of its schedule composed of reruns of since - discontinued Canadian lifestyle series . Among some of the more well - known Canadian television series among American viewers include the Degrassi High franchise (which aired in Canada on CBC Television, with the later incarnation Degrassi: The Next Generation airing on CTV and presently MuchMusic), Rookie Blue, SCTV Network and The Red Green Show . </P> <P> Programming from Japan has had a niche market in American television, with some anime programs (generally dubbed into English) having been seen on American television since the 1960s . The Power Rangers series was heavily edited from a Japanese live - action tokusatsu series, Super Sentai, with newly filmed bridging sequences involving American actors (as the action sequences were entirely done in full costume, those scenes only had to be dubbed). The success of Power Rangers led to a wave of tokusatsu adaptations in the mid-1990s, none of which survived beyond two years . </P>

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