Key-pad

The user presses the key on his key-pad corresponding to the required topic. […] If a viewdata user wanted to find out more information about a service, all he would do is key in the right code on his key-pad.

For example, mail-order applications enable users to indicate, by numeric code on their key-pads an item to be purchased and a credit card number to be debited.

In the 1970s, no educationist would have predicted the explosion in universal written communication caused by the personal computer, the internet and the key-pad of the mobile phone.