In the
comic book industy, and
ashcan is an
in-house mock-up of a upcoming
title. It is used to
secure copyright on a
work. As such, usually only a couple of them are made. They are often
black and white, and usually
smaller than a normal
comic book (4" x 5").
In more modern times, an ashcan is no longer used for securing rights. They are instead used as introductions to a new series. An ashcan often includes pre-production sketches, character designs, and creator interviews.
They are still normally printed in small quantities -- limited editions -- and many become collectors items.