The FCC's definition of "superstation" is a popular broadcast television station whose signal has been up-linked to satellite for redistribution by local cable systems outside the station's local and regional coverage area. The practice has since been restricted by the FCC, although seven stations that began superstation coverage prior to the ban (including WPCH) are covered under a grandfather clause.
In more recent years, premium cable refers to networks, such as HBO, Cinemax, Showtime, Starz and (prior to 1997) the Disney Channel, that scramble or encrypt their signals so that only those paying additional monthly fees to their cable system can legally view them (via the use of a converter box); however, premium services have the discretion to offer the service unencrypted in conjunction with a certain number of cable providers during a short-term free preview period to allow cable subscribers that do not subscribe to a premium service to sample its programming, the concept being that interested subscribers could consider subscribing to the pay service during the preview period. Since their programming is commercial-free (except for promotions in-between shows for the networks' own content), these networks command much higher fees from cable systems.
The origins of premium cable lie in two areas: early pay television systems of the 1950s and 1960s and early cable (CATV) operators' small efforts to add extra channels to their systems that were not derived from broadcast signals.
In 1975, HBO became the first cable network to be delivered nationwide by satellite transmission. Prior to this, starting in 1972, it had been quietly providing pay programming to CATV systems in Pennsylvania and New York, using microwave technology for transmission. HBO was also the first true premium cable (or "pay-cable") network. However, there were notable precursors to premium cable in the pay-television industry that operated during the 1950s and 1960s (with a few systems lingering until 1980), as well as some attempts by over-the-air broadcasters during the 1970s and 1980s.