aspect ratio

Aspect Ratio

The ratio of width to height for an image or screen. The North American NTSC television standard uses the squarish 4:3 (1.33:1) ratio. HDTVs use the wider 16:9 ratio (1.78:1) to better display widescreen material like high-definition broadcasts and DVDs. See this article about aspect ratio to better understand it and get pointers on troubleshooting some common aspect ratio problems.