HDTV, or high-definition television service, provides the ultimate home theater experience, with higher-resolution pictures, wider aspect ratios, and Dolby Digital Surround Sound.
A standard television is capable of displaying 480 lines, compared to HDTV's over 720 lines. Increasing these lines increases the resolution, which means you get a crisper and clearer picture. The images are incredible. The sound is fantastic...and going from regular TV to HDTV is as amazing as it was to go from black-and-white to color.