while teletext services were provided free of charge, and were encoded as part of the regular television transmissions, prestel data were transmitted via telephone lines to a set-top box terminal, computer, or dedicated terminal. while this enabled interactive services and a crude form of e-mail to be provided, gaining access to prestel also involved purchasing a suitable terminal, and arranging with a post office engineer for the installation of a connection point known as a jack 96a. (from the early 1980s, the "new plan" sockets were fitted as standard on new lines and on any change of rented handset, and terminals or modems then required no special connections.)