TiVos allow a user to specify programming to record by time, program name, genre, or other more complex parameters. Utilizing an internal programming guide (updated nightly via phone connection to TiVo headquarters), the TiVo selects and records the desired programming. Programming may be stored until the large internal hard disk is filled to capacity, at which time TiVo will dispose of older programs in favor of space to record new ones. This practice of automatically recording programs for later viewing is often referred to as time shifting.
Besides recording programs specified by the users, the units also can automatically record programs that are based on interests of the users; each time the users are watching a program, they can tell TiVo they favor that show or not. That is used as a profile and TiVo can start to record programs that might fit to preference to the users without explicitly specifying such programs. It was intended to change the way people watch TV.
In addition to recording specific programs, the TiVo unit constantly records the incoming television signal, allowing users to pause or rewind "live" TV within a short (generally 30 minute) buffer. This allows the users to watch shows that are still being recorded. The classic way to watch "live" TV with a TiVo is to start watching 10-15 minutes after the program you're interested in has started. Thus the TiVo has a 10-15 minute buffer built up that you can use to fast-forward through commercials as the program progresses. This is one of the most obvious advantages of TiVo over traditional VCRs. More seasoned TiVo users hardly ever watch live TV.
Another advantage over traditional tape based recorders is that users can watch a recording from TiVo as it records another program.
Despite its innovative functionalities and ease of use, TiVo has had a difficult time penetrating consumer markets as well as traditional Personal video recorders. Many of adopters of TiVo testify that they love TiVo so much that they cannot imagine watching TV without it. Still, TiVo has remained a niche product. Some argue that it is because consumers are unfamiliar with the benefits of a system like Tivo. It takes a few weeks of use to fully understand the magnitude of the change TiVo brings to television viewing. Another is likely the cost of the monthly or lifetime subscription fees.
The TiVo PVR, manufactured by Thomson, was launched in the United Kingdom in the autumn of 2000. As in the US it acquired a niche market position, selling about 35,000 units over the next year and a half. Although user forums have reflected the US experience of not being able to imagine watching TV without it they have also criticised the company for failing to run an effective advertising campaign to promote the TiVo system, with the result that the PVR went out of production in the UK in early 2002. The TiVo service continues to be provided to existing customers, and the price of second-hand machines with lifetime subscriptions has soared on online auction sites above the original market price of £400.
In contrast to other PVR companies, TiVo is well-known for the Apple Macintosh-like loyalty of their users.
Hardware anatomy
The TiVo unit was designed by TiVo Inc., which currently provides the hardware design, Linux-based TiVo software, and operates the subscription dial-up service (without which a late-model TiVo will not operate.) TiVo units are manufactured by various OEMs, including Philips and Sony, which license the software from TiVo Inc.
TiVo systems are based on PowerPC or MIPS processors, connected to MPEG-2 encoder/decoder chips and high-capacity IDE/ATA hard drives. A typical TiVo unit has one drive of between 20 and 80 gigabytes in size. The TiVo hardware can support two drives of less than 137 gigabytes each without major alteration. Larger drives can be used with the addition of a kernel upgrade; four drives can be used with the addition of a third-party hardware add-on card.
Some TiVo systems are integrated with DirecTV receivers. These DirecTiVo recorders are interesting because they record the incoming satellite MPEG-2 digital stream directly to hard disk without conversion. Because of this and the fact that they have two tuners, DirecTivos are able to record two programs at once. In addition, the lack of digital conversion allows recorded video to be of the same quality as live video. It also provides TiVo hackers access to pristine digital copies of television programming. DirecTiVo's have no MPEG encoder chip. They can only record DirectTV streams.
Some users are concerned about TiVo's ability to collect usage data from units via the telephone line; Tivo stipulates that (currently) all usage data is aggregated by zip code. Recently, some have complained about TiVo's aggressive remote software-update system, which has the capability to add and remove features without customer's specific authorization. Early TiVo units were marketed as being capable of functioning without a subscription to the TiVo service (although functionality would be markedly reduced.) Newer units are designed to be eventually non-functional without a connection, and customers who have had their older units remotely updated complain that TiVo is retroactively violating their promise.
Various groups exist to "hack" the TiVo box (Hack Wiki). TiVo has generally remained on good terms with these projects, although it has lately begun to clamp down on many of the "back doors" in the software.
Many users have had success in installing extra and/or larger hard drives in their TiVos to increase its recording capacity. Others have designed and built Ethernet cards, a web interface, and figured out how to extract video from their TiVos.
See also: interactive television