The first practical way to fix a photograph was released to the world entirely for free

In 1839, Louis Daguerre unveiled the daguerreotype: a process that fixed a sharp image on a silvered copper plate in minutes rather than the eight-hour exposures earlier attempts had needed. The French government bought Daguerre's process and gave it away, patent-free, to every country except Britain, and mass photography took off almost overnight.

— Beaumont Newhall, The History of Photography: From 1839 to the Present — Museum of Modern Art, 1937 (revised editions through 1982)
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