Traditional televisions, unlike most consumer electronics, have a relatively long lifespan. Many users are loath to purchase a new televisions when their current set works just fine. The system of HD standards also isn't very user-friendly. This issue is multifold-there are only a few "true" HDTV resolutions, not all sets support all resolutions, and the wide variety of new television technologies all add to the confusion for the average consumer who simply wants HDTV. While I can't do much to help with this problem on a grand scale, I can take some time to educate you, my dear readers.
First things first, DVDs aren't HDTV quality; let's just clear that up right now. While DVDs do offer a significant improvement over VHS tapes and standard cable broadcast, they are essentially half the resolution of true HDTV signals. DVDs run at a resolution of 720x480, which in geek-speak is often referred to as "480p." While DVDs will look much better on an HDTV set, especially if your DVD player converts the resolution to something HD-friendly, they don't do much to stress the capabilities of an HDTV. Full HDTV signals can come in one of three types-720p, 1080i or 1080p. These numbers represent the lines of resolution in a given HD signal. Higher is better, except in the case of 1080i. Understanding the differences between these resolutions is essential for anyone interested in HDTV, so brace yourself for technical jargon.
The highest quality HDTV resolutions are 720p and 1080p. They are "progressive scan" resolutions (hence the p), which means that they are displayed on the screen all at once, the same as your computer monitor. The lowest quality HD resolution is 1080i because it is "interlaced"-instead of being displayed all at once, the signal is split in half when it shows up on screen. Because of this, 1080i is theoretically the same as a "540p" signal, putting it far behind 720p and 1080p. Despite being a weak HD resolution, 1080i is still a marked improvement over what we're used to. It simply isn't the biggest improvement.
If you are looking to buy an HDTV set today, I recommend that you choose one with a minimum resolution of 720p, which is sometimes referred to as 1280x720. Though 1080p is superior, it isn't as affordable or as available as 720p. Stick with 720p for now and you'll be set for all there is to come. Speaking of what's to come, there are many products coming out in the near future that will take full advantage of HDTV sets. All of the upcoming video game consoles and next generation DVD formats are being created with HD in mind, and more HD channels are becoming available over satellite and digital cable daily.
I know that these numbers are very difficult to resolve into standards of quality, as they are concepts best experienced in person. If you are interested in HDTV and want to get a better idea of what I mean, visit an electronics store and compare the HDTV feeds on display. Next time, I'll look into the various types of HDTV displays, and how the technology will affect our notions of home entertainment. If we're getting a cinema quality picture at home, why go to the movies?