a ​large ​printed ​picture, ​photograph, or ​notice that you ​stick or ​pin to a ​wall or ​board, usually for ​decoration or to ​advertise something:

Wikipedia describes a poster as any piece of printed paper designed to be attached to a wall or vertical surface.  Carbon Colour produces posters which are individually colour balanced and can be printed on self adhesive, cartridge , .  

Typically posters include both text and graphic elements, although a poster may be either wholly graphical or wholly typogaphic. Posters are designed to be both eye-catching and informative. Posters may be used for many purposes. They are a frequent tool of advertisers (particularly of events, musicians and films),propagandists and protestors and other groups trying to communicate a message. Posters are also used for reproductions of artwork, particularly famous works, and are generally low-cost compared to the original artwork.

The modern poster, as we know it, however, dates back to the 1840s and 1850s when the printing industry perfected colour lithography and made mass production possible.

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