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
Philips PM5544 the most commonly used test cards, with only the SMPTE bars, the BBC Test Card F and the Snell & Wilcox Zone Plate coming close to its usage. The Philips Pattern was later incorporated into other test pattern generators from Philips themselves, as well as test pattern generators from various other manufacturers. The BBC occasionally used a slightly modified version called Test Card G from 1971 until the late-1990s in conjunction with Test Card F, and although it was also used by the IBA in the 1970s it eventually abandoned the Test Card G and developed its own test card