ANALOG: the technology in use for more than 50 years to transmit conventional radio and TV signals. Vinyl recordings and most cellular phones are examples of analog technology.

DIGITAL TELEVISION (DTV): refers to transmitting a broadcast signal by encoding it as zeroes and ones – the digital code used in computers. DTV can be compressed to provide four, five or more channels in the same bandwidth required for one channel of the current standard television. Calculators, computers, compact discs and the Internet are examples of digital technology.

ASPECT RATIO: The ratio of screen width to screen height.

BANDWIDTH: the amount of spectrum available to each communications licensee. For digital conversion, the "Grand Alliance" plan approved by the FCC calls for the allocation of 6 MHz (megahertz) of the broadcast spectrum for each television broadcaster. It can be used for one analog signal, or one HDTV signal, or four multicast digital signals, and/or data transmission.

DIRECT BROADCASTING VIA SATELLITE (DBS): consumers may receive programs via a pizza-sized dish that is locked onto one satellite source. The signal is NTSC, digitized and compressed via a proprietary format and decompressed by a set-top box. DBS brings up to 200 channels of digital video and audio programming with superior picture and CD-quality sound into the home.

HIGH DEFINITION TELEVISION (HDTV): a form that provides crystal-clear quality wide-screen pictures with compact disc-quality surround sound. The aspect ratio of HDTV pictures is 16:9 as opposed to today’s 4:3 format.

NATIONAL TELEVISION SYSTEMS COMMITTEE (NTSC): the group that set the analog television standard 50 years ago. The abbreviation NTSC is used to refer to the current standard.

SPECTRUM (ELECTROMAGNETIC SPECTRUM): a means of charting the order of radio and television signals in terms of their physical wavelength. A continuous range of frequencies in the earth’s atmosphere.

STANDARD DEFINITION TELEVISION (SDTV): offers the ability to transmit four or more standard-quality programs (equivalent to NTSC) instead of HDTV programs, using the same channel. SDTV also incorporates stereo sound plus a wide range of data services. It displays picture and sound without noise, ghosts and interference.