Participatory art differs from individually produced art in many ways. It always has an it always will. The things they have in common are that they both involve art being done in some way. They also both have an author. However, this is where the main difference comes in. Participatory art has many authors, while individually produced art has only one. Take for example the Hooter Symphony which consisted of a "celebration of mechanic noise (factory sirens, motors, turbines, hooters, ect) performed by hundreds of participants, directed by conductors signaling from the rooftops." This is an example of participatory art from the 1920's. The music they made was not composed by one single author it was put together by hundreds of creative people. This is similar to today's community based art project Post Secret. Hundreds of people make artistic post cards that reveal an anonymous secret of theirs. They mail the post cards to one person, who then compiles them into a book. The book does not have just one single author it was put ogether by hundreds of creative people, just like the Hooter Symphony.