The impetus for a more complex type of television remote control came in 1973, with the development of the Ceefax teletext service by the BBC. Most commercial remote controls at that time had a limited number of functions, sometimes as few as three: next channel, previous channel, and volume/off. This type of control did not meet the needs of Teletext sets, where pages were identified with three-digit numbers. A remote control that selects Teletext pages would need buttons for each numeral from zero to nine, as well as other control functions, such as switching from text to picture, and the normal television controls of volume, channel, brightness, color intensity, etc. Early Teletext sets used wired remote controls to select pages, but the continuous use of the remote control required for Teletext quickly indicated the need for a wireless device. So BBC engineers began talks with one or two television manufacturers, which led to early prototypes in around 1977–1978 that could control many more functions. ITT was one of the companies and later gave its name to the ITT protocol of infrared communication.