TiVo is becoming synonymous with the digital video recorder, a VCR-like device that records TV shows to an internal hard drive instead of a removable tape. Like competitors ReplayTV and UltimateTV, TiVo offers a user interface on top of the basic DVR technology that allows users to record a program based on its name, rather than its time slot.
It doesn’t matter when something is on. Users can set up a favorites list and tell the DVR to record, for example, “Friends” whenever it appears on NBC. (It won’t record the syndicated reruns on other channels unless you ask it to.)
Of course, that’s something a VCR is capable of doing — unless “Friends” happens to be a special one-hour show or maybe airs on a Tuesday instead. Your VCR won’t know about the change but TiVo will. More here.