Networks: In the US, there are five major English-language television networks: ABC, CBS, CW, FOX, and NBC, in addition to the Public Television Service, a network of non-commercial educational and public television stations. Beyond this, there are several minor television networks, such as MyNetworkTV, ION, and Spanish-language Univision and Telemundo.
Cable & Satellite Stations
Pay television emerged in the United States by the late 1970s, led by networks such as TBS and HBO, and quickly exploded in popularity. Many of the most critically and commercially acclaimed programmes of recent years have originated not from the broadcast networks, but from cable television.
Satellite television is available in the United States, but for a variety of reasons, hasn't come to dominate the market ala Sky in the UK. The vast majority of the population receives pay television through cable, and most pay networks are referred to as "cable channels".
Local Stations - Major Market - New York City
Local Stations - Major Market - Philadelphia
Local Stations - Major Market - Los Angeles
Local Stations - Major Market - Washington D.C.
In no particular order, here's a selection of other local stations across the United States.