The Yamaha Playcard was a system used by several Yamaha electronic keyboards to playback music. The cards consisted of a large card (a bit smaller than A4 size) with musical notation, and a magnetic stripe on the lower edge. The stripe was read by swiping the card through a slot on the back of the keyboard (which could also act as a holder for the piece of music). The keyboard could then either playback the music, or play an accompaniment and the user could play the tune by following the music or pressing the keys that were lit by an LED.
Playcards were introduced around 1982 and were used by the PC-100 as well as some other models of Yamaha keyboards. The system was not used by any other keyboard manufacturers.
A number of different themed sets of Playcard were available, covering genres such as popular songs, classics, standards and show tunes. Judging by the songs included, Playcards don’t seem to have lasted beyond the mid-1980s.