DVD technology has been around a long time, over fifteen years, actually. Even with the introduction of blu ray disc, DVD is still essential in your own home theater design. Todays display technologies have evolved, and so has dvd technology right along with them.
Even in the best home theater design built today, the DVD player is an important piece of equipment.
DVD technology was a breakthrough for home theater systems that allowed a disc the same size as a CD to hold so much more information. This enabled high quality standard definition video and multi-channel audio to be recorded on a single disc.
At first, DVD players were designed to replace VCRs as the new way to watch movies. In the mid nineties, there was no high definition TV in the USA, just regular standard definition picture. DVD players were able to offer a far superior picture quality to VHS tape with roughly twice the resolution. 720 X 480 (DVD) vs. 320 X 240 (VHS). These numbers refer to the vertical and horizontal lines of resolution the two technologies can display.
With regard to picture quality, televisions have advanced, and DVD has advanced with them. First it was with progressive scan players. These players allowed playback of DVD discs to scan all of the horizontal lines in sequence vs. having to interlace the odd number and even number lines separately as televisions did to display their images. The process of displaying a picture with odd and even frames intermittently is called interlacing. To better understand this, visit the display resolutions page.
With the advance to high definition television (HDTV), DVD players have held on by improving their own capability to output higher resolution pictures. Some players even output up to 1080p resolution to maximize their picture quality on todays sophisticated TVs that can display it. This process is called up-converting or up-scaling, and it allows the DVD player to produce a sharper picture from a lower resolution source. Now while this picture will look great, it will not be as sharp or amazing as an image produced by a blu ray disc.
Remember, if you are concerned about the idea of purchasing both types of players, you don't have to. A blu ray player is also an up-scaling DVD player as well, sometimes referred to as a blu ray dvd player.
The bottom line? With thousands of great movie titles to choose from and prices falling all the time, DVD players and discs will be a mainstay of home theater systems for a while. Even with blu ray, high def satellite, and high def cable TV, an up-converting DVD player can be had for under $100!