"Play School" was, unintentionally, the first program to be broadcast on BBC 2 in the UK. A grand opening for the channel was planned for the previous night, but was stopped by an unexpected power failure.
Of almost 5700 editions aired between 1964 and 1988, just 1900 are currently known to survive.
A short film would be shown to viewers introduced through a choice of a round window (indicating a water subject), a square window (for an industrial one) or an arched window (other).
The windows (circle, square and arched) have recently reappeared in pre-school favorite Tikkabilla (2002), currently shown on BBC2 and UK digital channel CBeebies. This usually signaled either a short film or story time. Today its use is very much similar to the 1960s concept, heralding story time rather than video and story time.
In the 1960s, a clock was used to tell the time. Similarly to the windows, Tikkabilla (2002) uses the clock to tell the time.