Allan Kaprow (1927–2006) was an American artist.
For a historical example, Allan Kaprow, often considered the inventor of happenings, which is the performances of the '50s and '60s, had a piece where it was essentially refrigerator magnets, where you have those words that you can combine to make sentences. Only these were like cards of paper.
Jon Ippolito, Preserving Digital Art: Regina Harsanyi, Jon Ippolito