Why is HD different from analog television?

Question

What makes HD different from regular TV? not the picture, but the actual technology?

Answer 1

This may help you understand more:

http://en.wikipedia.org/wiki/Digital_tv

Oh yeah, this too:
http://en.wikipedia.org/wiki/Hdtv

Answer 2

Analog TV signals are based on 1930's technology. All the information in the signal is continuously changing and at any instant in time can have a large number of possible values.

A digital TV signal is based on 1990's technology. The information is sent as a stream of computer like data. The data is in digital form. There are specialized computers on both ends of the process that incode and decode the signal.

Much more information can be sent on a particular TV channel using the digital method, so it's possible for each channel to carry both HD & SD programing.

In both analog & digital TV, the video information is modulated on a much higher frequency electromagnetic signal so it can be transmitted over the air. In the US the same frequencys are used for both digtial and analog TV broadcasts, so the same TV antennas can be used. From the antenna's view point, there is no difference between digital and analog TV broadcasts.

Answer 3

First not ALL Digital TV is HD, but HD is digital TV.

Think of analog TV as AM/FM radio, except instead of sending a song, you send scan line by scan line a TV picture.

Think of digital TV as sending over JPEG's (except more efficiently).

In digital TV each frame is digitally captured compressed and send as 0's and 1's.

Answer 4

HD is more better beacouse its a better vison and its like ourealy there at the place