The switch to digital TV promises several benefits:

Viewers should notice improvements in picture and sound quality, particularly in the case of high-definition (HDTV) broadcasts. (To get the full effect, you’ll need a high-definition set, and the broadcaster and, if applicable, cable or satellite provider must provide a high-definition signal.)...

The difference between Analog TV and Digital TV boils down to the way the TV signal is transmitted. Standard analog TV is transmitted in a manner similar to radio.

In fact, the video signal of analog television is transmitted in AM, while the audio is transmitted in FM. Analog TV is subject to interference, such as ghosting and snow, depending on the distance and geographical location of the TV receiving the signal....

Digital TVs have labels as “Integrated Digital Tuner,” “Digital Tuner Built-In,” “Digital Receiver,” or “Digital Tuner,” “DTV,” “ATSC,” or “HDTV” (High Definition television). If your television equipment contains any of these labels or markings and it contains a digital tuner, you can view over-the-air digital programming without the need for a digital-to-analog converter box.

The only televisions that have DTV turners are those that since about 1998, have been sold as having an integrated or “built-in” DTV or HDTV broadcast turner. (An HD set sold as a “monitor” or “HD-ready” is capable of displaying HDTV but does not have a built-in HDTV turner) Most TVs with analog turners are now required by the FCC to also be marketed with built-in or separate DTV or HDTV turners – this will soon be a requirement for all TVs....

There are many quality levels of digital television programming. The most common are:

Standard Definition TV (SDTV) - SDTV is the basic level of quality display and resolution for both analog and digital. Transmission of SDTV may be in either the traditional (4:3) or widescreen (16:9) format....

A Digital to Analog Converter Box or Digital Television (DTV) Converter Box is an electronic device that converts the new free over-the-air digital signal into an analog signal viewable on older “analog” television set. A digital to analog converter box will not give you a digital picture on an analog TV set, but will not convert your analog TV set into a high definition TV, also known as a HDTV.

A TV converter box is a stand-alone device that allows your antenna to receive and convert digital signals into a format analog television sets can display. A DTV converter box hooks up to your analog television set and over-the-air antenna. The box converts the digital television signal into an analog format, making it viewable on your analog TV set. Several of these devices have already been shown and, while few were initially available, they are becoming more available by the day.
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The benefits of digital television are amazing and include:

Better picture quality: Digital technology allows the transmission of pictures with higher resolution for dramatically better picture and sound quality than currently available (HDTV). Most viewers will see improved clarity and color when watching their favorite news, sports or entertainment programming....

Digital Television or DTV is new technology that will replace today's analog television system. DTV is more efficient and more flexible than the traditional way of broadcasting known as analog. Digital television allows higher-quality images and sound and more programming choices than analog television does. However a digital signal does not necessarily carry a higher-quality image or sound than an analog signal.

DTV enables broadcasters to offer television with better picture and sound quality., DTV makes it possible for stations to broadcast multiple channels of free programming all at once, called multicasting, instead of broadcasting one channel at a time. DTV technology can also be used to deliver future interactive video and data services that analog technology can’t provide.
DTV offers several broadcast options, two of which are considered to be HDTV formats. Some of the more common DTV standards include:...