However, if you think that digital TV stops at the U.S. border then you would be wrong. Digital TV has no border as many nations either already converted or will convert to digital TV at some point in the near future.
Standard Definition and High Definition
There are two types of digital TV that you’ll encounter when watching TV – standard definition (SD) and high definition (HD).
Standard definition is a lower form of digital TV. The aspect ratio for SD TV is 4:3, which is more square-like in appearance. That’s why when watching SD images on a HDTV you’ll get either a stretched picture or a picture with black bars on the side of the screen.
High definition is the highest form of digital TV. The aspect ratio for HD is 16:9, which is rectangular like a movie theater screen. That’s why when watching HD images on an analog or SDTV that you’ll get black bars on the top and bottom of the screen.
Do I Need a New TV To Work with Digital TV?
No, but if you use an antenna and own an analog TV then you will need to buy a DTV converter box. The same applies to anyone that wants to use a VCR to record digital TV signals regardless of the TV type.
Even if you have a HDTV you'll need a converter box to record on a VCR. That's because the tuner inside the VCR doesn't work with digital TV. If you don't want a converter box then my advice is to buy a digital video recorder or DVD recorder.
Do All Stations Broadcast Digital TV Now?
All full power stations broadcast in digital but there are stations that still broadcast in analog -- Class A, Low Power, and Translator.
Are All Programs Broadcast in High Definition (HD) Digital TV?
No. The majority of daytime programming and late-night programming is in standard digital - the square format.
The amount of HD content is increasing but we're not close to watching all-HD TV. It's way too expensive for every production company and broadcast station to convert completely to HD. In addition, there is far too much analog programming to throw away.
Why Do Some Stations Have Multiple Channel Numbers?
The channels will look something like 24.1, 24.2, 24.3, etc. This is a great thing about digital TV -- the ability to multi-cast.
These secondary channels are called digital sub-channels. At this time you can only get sub-channels with an antenna.
