Digital TV vs cable
Before the advent of digital television, it was simple to understand the difference between cable and regular TV. In 2011, however, with the replacement of analogue broadcast television by standard digital television, and also with the advent of high-definition digital cable, it's easy to confuse the terms and misunderstand which is which.
Digital television (DTV) has replaced analogue television as the broadcast method for television stations. DTV allows television stations to broadcast their content with better picture and sound quality, as well as enabling stations to broadcast on multiple channels. DTV benefits viewers by offering not only better picture and sound, but also a wider variety of television programming. Unlike cable television, digital television is free.
Cable television, also known as Community Antenna Television (CATV), provides programming to televisions connected to a community antenna by a cable. This is a paid service that consumers receive via subscription to a cable television provider, and it generally includes different levels of service, beginning with basic. Basic cable packages usually include a combination of local programming and specialty channels that aren't broadcast over the open airwaves like DTV channels. Premium cable packages usually include specialized programming, such as movies and sports.
HD Digital Cable
To confuse matters, there is also digital cable. This is cable television that, like DTV, is broadcast via a digital signal rather than an analogue signal. Digital cable is also broadcast in high definition (HD), providing the clearest picture on HD-enabled television sets.