Outsider art describes artwork created by artists who live outside the boundaries of official culture. Outsider artists have limited or no contact with mainstream art institutions.
Specifically, outsider music refers to songs by musicians who don’t belong to the commercial music industry. These songs often ignore standard compositional conventions (either deliberately or because the musician is untrained).
The Shaggs, formed in 1968 in rural New Hampshire, are an example of outsider music. The band was comprised of three sisters whose father, Austin Wiggin, believed that his daughters were called to create a band.
The Shaggs’ music can be pretty difficult to listen to, especially because the drums are not in time with the guitar and everything is out-of-tune: