The history of the photocopier (also known as a copier or copy machine) is the history of making copies External -- and paperwork. Before modern advances, the desire for multiple copies of an item meant clerks duplicating things by hand. But the advent of carbon paper, the typewriter, mimeograph machine, and photocopier meant more copies could be made faster.
In 1937 Chester Carlson invented a process called electrophotography (later renamed Xerography) and he began by working with the Battelle Memorial Institute. Eventually Haloid Corporation, later XEROX Corporation, licensed the right to develop and market a copying machine and called the new machines "Xerox Machines." The 1970s saw the introduction of color, and eventually other functionality like collating, double-sided copies, incorporating alternate paper sizes, and stapling that made the machines even more versatile.
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