"Mail Art" is hard to define as one thing because every mail artist would give you a different definition. Essentially, it's a big international network of people who exchange artwork and ideas via the postal service. Mail art in simplest terms is one person sending another person something that they have created. In more complex terms, there are mail art shows where hundreds of people send in work according to a specific theme. All of the work that is sent in is displayed in some manner and everyone who participates gets "documentation"--a list of all the artists, and possibly a catalog of the artwork. Announcements for these shows are distributed within the network (often to people who have participated in past shows), and not from any central location. It is democratic art at its best. Pop artist Ray Johnson is considered the originator of the network- in the 1950's he shunned the gallery-dealer-museum system of conventional art and started sending his artwork to people for free, often for no apparent reason. Sometimes he would prompt the recipients to change the piece in some way and pass it on to a third person, setting in motion a chain of contact which continues to this day. Ray Johnson committed suicide in 1995, but some of the pieces which Ray originated are still in circulation. Mail art seeks to break down the division between audience and artist-- anyone can be a mail artist, and have their work shown in a mail art show, regardless of academic credentials or technical skill- all you need is a stamp.