Tv Buyers Guide. Our online TV buyers guide summarizes the important features of TVs from standard-definition TVs (SDTV)to high definition TVs (HDTV)...

TV Buyers Guide

Standard-definition TV (SDTV)

This is the kind of TV most of us own right now. It's big, it's boxy, it's blurry, and it's soon to be a thing of the past. Here's what you need to know about SDTV.


SDTV is the oldest technology and will likely be the least expensive type of TV in the store. If you're happy with technology from the last century, then SDTV is fine.

Enhanced-Definition TV (EDTV)

The EDTV scanning rate is 31.5 KHz, exactly twice as powerful as NTSC. EDTV draws all 480 horizontal lines one after the other, rather than all the odd ones followed by all the even ones. The effect for the viewer is dramatic. The scanning lines aren't nearly as visible as they are with SDTV. Simply put, EDTV is twice as good as SDTV.

High Definition TV

HDTVs will scan at NTSC rates (15.75 KHz), EDTV rates (31.5 KHz), and even higher rates. This is because new high-definition TV signals require more scanning lines than either SDTV or EDTV.

Higher resolutions, such as 720p and 1080i, offer much, much sharper pictures than SDTV or EDTV. Watching a TV of this quality is more like looking out a window than looking at a TV program.