BBC teletext service, Ceefax, was introduced, created initially to provide subtitling, but developed into a news and information service. In 1978, BBC staff went on strike just before the Christmas of that year, thus blocking out the transmission of both channels and amalgamating all four radio stations into one. Since the deregulation of the UK television and radio market in the 1980s, the BBC has faced increased competition from the commercial sector (and from the advertiser-funded public service broadcaster Channel 4), especially on satellite television, cable television, and digital television services. In the late 1980s, the BBC began a process of
Teletext comparable to systems such as France's Minitel. The modem was asymmetric, with data sent at 75-bit/s, and received at 1200-bit/s. This two-way nature allowed pages to be served on request, in contrast to the TV-based systems' sequential rolling method. It also meant that a limited number of extra services were available such as booking event or train tickets and a limited amount of online banking. Teletext information is broadcast in the vertical blanking interval between image frames in a broadcast television signal, in numbered "pages." Teletext allows up to eight 'magazines' to be broadcast, identified by the first digit of