What is HDTV?

Summary

HDTV stands for High Definition Television. The High part comes from the increased number of pixels as compared to Standard Definition Television (SDTV). Pixels are the smallest parts of picture. The more pixels a picture has, the more detailed the picture will be.

HDTV requires more transmission bandwidth, which is why the United States is moving to all digital broadcasts in Feb 2009. A digital signal allows the data to be compressed, which allows the signal to hold more data.

Different types of HDTV (and SDTV)

Resolution Total Pixels Aspect Ratio HD or SD
480i/p 720x480 345,600 3:2 SD
720p 1280x720 921,600 16:9 HD
1080i 1280x1080 1,382,400 16:9 HD
1080p 1920x1080 2,073,600 16:9 HD