Hard-disk based DVRs

The two early consumer DVRs, ReplayTV and TiVo, were launched at the 1998 Consumer Electronics Show in Las Vegas. Microsoft also demonstrated a unit with DVR capability but commercial availability of this software would have to wait until the end of 1999 for full DVR features in Dish Network's DISHplayer receivers. TiVo shipped their first units on March 31, 1999, and to this day the last Friday in March is celebrated as a company holiday known as 'Blue Moon'.[2] Although ReplayTV won the "Best of Show" award in the video category[3] with Netscape co-founder Marc Andreessen as an early investor and board member[4], it was TiVo that went on to much greater commercial success. While early legal action by media companies forced ReplayTV to remove many features such as automatic commercial skip and the sharing of recordings over the Internet[5], newer devices have steadily regained these functions while adding complementary abilities, such as recording onto DVDs and programming and remote control facilities using PDAs, networked PCs, and Web browsers. The label PVR has almost fallen completely into disuse in the US trade news media (it is still use in the United Kingdom) in favor of the more popular DVR descriptor. The name PVR never really caught on, although its use has not entirely vanished. As of December 29, 2008, Armstrong Cable still uses PVR terminology.[citation needed]

Hard-disk based DVRs make the "time shifting" feature (traditionally done by a VCR) much more convenient, and also allow for "trick modes" such as pausing live TV, instant replay of interesting scenes, chasing playback where a recording can be viewed before it has been completed, and skipping of advertising. Most DVRs use the MPEG format for compressing the digitized video signals. When there is recorded time left to be played it is often referred to as "future credit" or "the power".[citation needed] Despite the yearnings of customers, one cannot purchase more "future credit" from a service provider.