
The simplest DVRs will just act as a VCR might; serving as a TV or VHS recorder with basic timer functions. Other, more complex DVRs feature a wide variety of recording and playback options, which often includes full channel listings and guides.
The amount of video that a DVR can record depends on its hard drive size. Generally speaking, one hour of quality video can be recorded for each gigabyte of storage space. Thus, a 200GB model would be able to store 200 hours of video at high quality, and perhaps double that at lower (but still viewable) quality. To learn more, check out the articles below.
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