Some NTSC television sets can display a picture 720 pixels wide by 486 pixels high. That's a total of 349,920 pixels. It sounds like a lot, but it's pretty low resolution compared to computer monitors where the resolution is often 800 x 600 or better. The reason you may not have noticed the difference in quality is because the image on the television screen is constantly changing, and you don't have enough time to see much detail.

When you see your first High Definition TV, however, you'll notice the difference. HDTV can have a resolution of up to 1920 x 1080. That's 2,073,600 pixels, or six times more pixels than the older resolution. So, when you look at comparable sizes of HDTV and NTSC sets, the HDTV set will have smaller, square pixels, and more of them. Images will be crisper and cleaner, with more detail in every close-up and every panorama.

A nicer picture is all well and good, but why do we need digital? Let me tell you why.

Why Digital?