Widescreen (16:9) vs. Standard Screen (4:3)
The TV you grew up with had a nearly square picture tube--the ratio of width to height is 4:3. HDTV uses a 16:9 screen, delivering a panoramic view of movies and other wide-screen content. While there are still some high-def sets with 4:3 screens (they show wide-screen content with black bars at top and bottom), true 16:9 sets are the only serious contenders.