Philips CD-i console, also known as Green Book, which was co-developed by Philips and Sony. In addition to games, educational and multimedia reference titles were produced, such as interactive encyclopedias and museum tours, which were popular before public Internet access was widespread. The CD-i was also one of the earliest game systems to implement Internet features, including subscriptions, web browsing, downloading, e-mail, and online play. This was facilitated by the use of an additional hardware modem and "CD-Online" disc (renamed Web-i in the US), which Philips initially released in Britain in 1995 for $150 US. Development of the CD-i format began in
Video CD audio frequency range is limited to those sounds most clearly heard by the human ear. The VCD standard also features the option of DVD-quality still images/slide shows with audio, at resolutions of 704×480 (NTSC) or 704×576 (PAL/SECAM). Version 2.0 also adds the playback control (PBC), featuring a simple menu like DVD-Video. Shortly before the advent of White Book VCD, Philips started releasing movies in the Green Book CD-i format, calling the subformat CD-i Digital Video (CD-i DV). While these used a similar format (MPEG-1), due to minor differences between the standards these discs are not compatible with VCD players. Philips'