Glossary Of Terms

Analog TV:

The technology that has been used for the past 50 years to transmit conventional TV signals to consumers.

Closed Captioning:

Service that allows persons with hearing disabilities to read dialogue or the audio portion of a video, film or other presentation on the TV screen.

Datacasting:

The ability to broadcast data in addition to program material allowing viewers the ability to download data (text, graphics, maps, services) to specially equipped computers, set–top boxes or DTV receivers.

Digital Television (DTV):

The umbrella term encompassing high–definition television and several other applications, including standard – definition television, datacasting, multicasting and interactivity.

DVD:

"Digital Versatile Disk" (formerly Digital Video Disk). An optical disc that can play back video on demand.

HDTV:

High-definition television. This displays the highest–quality level of digital television, with clear, sharp, colorful images and surround sound in a wide–screen (16 x 9) movie–like format. You need an HD TV set to see the full effect, but you can receive HD on an analog TV set with a converter box.

Multicasting:

Digital technology allows each digital broadcast station to split its bandwidth into two, three or four or more individual channels of programming and/or data services.

Set–top converter box:

The unit that connects to an analog TV, receives the digital TV signal and converts it to an analog signal that the TV can display.

SDTV:

Standard–definition television. Digital formats that do not achieve the video quality of HD, but are at least equal, or superior to, analog pictures. SDTV may have either 4 x 3 or 16 x 9 aspect ratios, and it includes surround sound. Often described simply as "SD."

Simulcast:

The broadcast of the same program simultaneously over two or more different systems or channels.

Widescreen:

Term given to screens with a wider aspect ratio than 4 x 3. Digital HDTV is 16 x 9 widescreen.