Art forgery is the creating and selling of works of art which are falsely credited to other, usually more famous, artists. Art forgery can be extremely lucrative, but modern dating and analysis techniques have made the identification of forged artwork much simpler.
In summer 2009, ARCA - the Association for Research into Crimes against Art - began offering the first postgraduate program dedicated to the study of art crime. The Postgraduate Certificate Program in Art Crime and Cultural Heritage Protection includes coursework that discusses art fakes and forgery.
More information on the Wikipedia page  which includes details of the background of the topic, and how forgeries are identified: there are also various external links.
The relevant Wikimedia Commons Category is .