One of the first questions that must be answered is: What is HDTV? Here is a brief overview.
Simply stated HDTV is 100% digital television delivered in a high resolution format. This does not mean that all digital TV is HD but all HD is digital. Digital simply refers to how the signal is transmitted to you. There is a bit of confusion about what the true resolution is for HDTV but the answer is really quite simple, as long as the resolution is listed as 1280x720 (also listed as 720p) or higher it is HDTV. Two other common resolutions are 1024x1080 and 1366x768. The two most common are usually listed as 720p and 1080i. Notice that this is the last number in the listed resolution. This number refers to the number of lines that the television can display on the screen. A standard analog television can only display 480 lines on the screen, so you can see that HDTV displays roughly double or more lines on the screen. This translates to a much sharper and more realistic picture. It is important to note however that you can not judge a HD television on these numbers alone. How the television actually displays these lines, such as the brightness, scaling, and video processing to name a few, make a huge difference when making the decision of which HDTV is best for you.