The most common high definition formats are: 720p and 1080i. The 720p format makes a picture with 720 vertical lines, each with 1280 pixels horizontally. It uses progressive scanning, like computers, which sends a complete picture 60 times per second. The 1080i format creates a picture with 1080 vertical lines, each with 1920 pixels horizontally. 1080i uses interlaced scanning, like traditional TV, which alternates sending odd lines and even lines and thus sends a complete picture 30 times per second. Both formats make for a clearer, sharper picture than analog television.

1080p resolution is a fairly new format that is 1080 lines of progressively scanned video. A television set's inputs must be able to process a 1080p signal and be designed to accept 1080p/24/30/60 fps signal from an external 1080p progressive source.

DTV is the umbrella term used to describe the new digital television system adopted by the FCC in December 1996. DTV is a new way of transmitting television signals. It will eventually replace analog, the way television has been transmitted for the last 50 years. HDTV uses the entire channel and offers superior picture and CD quality sound.

No. Digital programming can either be in standard definition (SD) or high definition (HD). Standard definition broadcasts can have a format of either 480i or 480p. High definition broadcasts can be e720p, 1080i or 1080p format.

The first noticeable difference of high definition TV from the analog television system is that the screen is much wider. With analog TV, the width of the picture is divided by the height of the picture and will always produce a 4/3 ratio. High definition television, on the other hand, has a width to height ratio of 16/9, which closely approximates that of a movie screen. The second advantage is that HD has over six times the sharpness and clarity of analog TV. The HDTV picture contains 1080 vertical picture elements (pixels) by 1920 horizontal pixels for a total of over 2.0 million pixels. The current standard definition picture contains only 480 vertical pixels by 720 pixels for a total of 345,600 pixels. Third, the color resolution of HDTV is also more than twice the resolution of analog. High definition television also has six channels of CD-quality surround sound (left, right, center, left rear, right rear, and low frequency effects).

TitanTV takes a member's street address and predicts the digital over-the-air stations one can expect to receive. Programs available in high definition are marked with a red HD symbol in the program grid cell. In addition to providing listings and HD designation information for over-the-air channels, TitanTV also provides this information for digital cable and satellite lineups.

First, you need a digital TV and a digital TV tuner. You can buy the tuner and display in an integrated DTV, with both built in. If you purchase a DTV monitor (an analog TV with the capability to display DTV) you will need to buy a DTV tuner in a separate set-top box. DTV tuners can be included in a DTV satellite receiver, a DTV capable digital cable box or an over-the-air DTV tuner.

Second, you must be able to receive a digital signal at your location. Depending on where you live, DTV signals can be delivered through digital cable, digital satellite or an over-the-air antenna that receives digital signals. TitanTV provides a comprehensive list of the digital channels available at your address. To receive a free over-the-air signal, you will need an over-the-air antenna. The type of antenna required depends on your location and distance from transmitters and local terrain. In many instances, a rooftop antenna will be most effective. To find out what antenna works for your home, use TitanTV's antenna selector section.

Third, a program must originate in HDTV and be broadcast in HDTV. Just because you have an HDTV set and signal does not mean that everything you watch will be in High Definition. And just because a program arrives through a digital cable or a digital satellite does not mean it is in HD. Much of the programming today, even that received from a digital satellite, digital cable, or even a digital channel broadcast over the air, is delivered in what is known as standard definition. You will get a better picture than you would get with the analog broadcasts TV has used for all these years, because a digital picture will be free from the ghosts and snow that can plague analog transmissions. A standard definition digital picture will be good, but not nearly as sharp and crisp as HD.

There are different types of high definition TV sets suited for various room layouts, budgets and priorities:

• Flat-panel LCDs and plasma TVs offer space-savings but may be more expensive than other options.
• Rear projection TVs offer large images at more affordable prices but may not fit in certain rooms given their size.
• Front projectors offer the largest HD images but room brightness have adverse effects on the overall viewing experience.
• Direct-view HDTV sets offer reliability of television picture tube technology but also can be fairly large in size.

The foundation of the Plasma TVs is over a million tiny glass cells that are charged with a mixture of neon and xenon. Behind these cells are colored phosphors, which are chemical compounds that emit light when energized. Each cell has three phosphors; one red, one blue, and one green. When activated by an electrode, the plasma cells emit invisible UV light. The UV light strikes the red, green and blue phosphors on the back of the display and thus creates the pixels that form the image you see on the screen.

LCD (Liquid Crystal Display) technology works differently. Liquid is suspended between two transparent panels. Within the liquid are crystals that, when activated by voltage, re-position themselves so that they either allow the light to pass through the panel and/or block the light. This process is similar to turning on and off a million light bulbs. Fluorescent tubes behind the panels supply the light source. Both the lit and unlit crystals create visible pixels that cumulatively compose the image on the screen.

A digital signal has the capability for up to19.4 Mbs of content allowing a station to provide multiple Standard DTV channels in digital, a process called multicasting. This means that a station can transmit multiple channels in the same bandwidth instead of just one.

The FCC has assigned a digital or RF channel number to all digital stations. In addition, some local affiliates are using Program and System Information Protocol (PSIP) to remap to their analog channel numbers. PSIP is data that is transmitted along with a station's DTV signal that tells DTV receivers important information about the station and what is being broadcast (what channel to tune to for reception of the station, helps maintain current (analog) channel number branding, tells receiver whether multiple programs are being broadcast, etc.).