postcard
n.
A card, commonly 4 × 6 inches, used for sending short messages through the mail.
Notes
Postcards made after 1906 often have an illustration on one side. A real photo postcard has a photographic image, as opposed to a picture postcard, which has a photomechanical or printed image.
Citations
Levy 2001, p. 87 The invention of the postcard created a form where brevity would be the rule rather than the exception. After a short period of experimentation in the private sector, the first postcards used on a mass scale were created by national governments by Austria in 1869, by Britain in 1870, and by the United State in 1873. At the international postal congress the following year, it was agreed that cards, although varying in size from country to country, could cross national borders without being restamped.
