Have you been thinking about getting a digital video recorder (DVR) but not sure just how the system works? Maybe you think this technology is changing too rapidly and it's not worth buying - maybe you think DVRs will become the next 9-track player. Well, technology is certainly changing rapidly but DVRs are here to stay.

Basically, a DVR is a hard drive with a few special functions. The hard drive resides in a box with a computer board, memory, and a central processing unit. On the back of the box are a series of jacks. These jacks allow the hard drive to receive input through a coax cable (from your satellite dish.)

The satellite dish sends a digital signal (MPEG-2, the compression standard used to fit a large volume of information onto a hard drive), to the hard drive for storage. When you decide you want to watch the show you recorded, the show is accessed on the hard drive and sent via cables to your TV.

The hard drive is driven by a computer program. The computer program is the operating system for the recorder. In the case of a TiVo brand recorder, the operating system is a modified Linux installation. This computer program is a little more sophisticated than the VCR programs of old. Instead of just recording on a time comparison basis, the DVR actually compares it's programming information to the satellite TV service provider. So the viewer is able to program the system to record all of a favorite show (for example, all M*A*S*H reruns) and the DVR will search up to 14 days of programming from the satellite. When it finds the program being played, it will record it, regardless of time or channel.

Another special feature of the DVR is the ability to play live programming and let the viewer pause, rewind, or fast-forward through the live broadcast. How does that work? Well, back to the hard drive. The hard drive is partitioned to allow a small recording space that is for live broadcasts. These broadcasts are being recorded to the 'live' section of the hard drive. So if the viewer chooses, they can pause the live program - essentially pausing the hard drive replay, and then pick up in a few minutes.

If the system became any simpler, you wouldn't even need to type in your preferences, it would just be accomplished through a simple brain scan. Oh well, it appears there are some technology changes for the future. In the meantime, DVRs are a great addition to any home entertainment system.