Chock-A-Block was a BBC children's television programme, first shown in 1981 and repeated through to 1989 and shown as part of the children's programme cycle See-Saw. "Chock-A-Block" was an extremely large yellow computer, modelled to resemble a mainframe of the time; it filled the entire studio and provided the entire backdrop for the show. The presenter of the show supposedly played the part of a technician maintaining the computer; there were two presenters, Fred Harris and Carol Leader, but only one appeared in each episode. At the start of the show, the presenter would drive around the studio towards the machine in a small yellow electric car, before saying the catchphrase "Chock-A-Bloke, checking in!".

The presenter would then use the machine to find out about a particular topic. The name "chock-a-block" was supposedly derived from the machine's ability to read data from "blocks" - which were just that, physical blocks painted different colours. A typical show would include dialogue from the presenter, a brief clip played on Chock-a-block's video screen, and the presenter recording a song on Chock-a-block's audio recorder.