Xerox art (sometimes, more generically, called electrostatic art or copy art) is created by putting objects on the glass, or image area, of copying machine
and by pressing "start" to making an image. If the object is not flat,
or the cover does not totally cover the object, the image is distorted
in some way. The curvature of the object, the amount of light that
reaches the image surface, the distance of the cover from the glass all
affect the final image. Often, with proper manipulation, rather ghostly
images can be made. Xerox art appeared shortly after the first Xerox copying machines were made. There are exhibits now in Los Angeles and New York City museums of more controlled examples of the form. It is akin to photography. Color copiers added to the form, as can be seen by surrealist Jan Hathaway's combining color xerography with other media, or Carol Heifetz Neiman's layering prismacolor pencil through successive runs of a color photocopy process (1988-1990).
The San Francisco Bay Area had an active Color Xerox arts scene
starting in 1978 many local artists worked in the medium. From post card
stores to gallery exhibits, to Barbara Cushman's Color Xerox Calendar
this was a busy time for copy art.
Xerox art is often used in mail art.