must_know:
OCR - Optical Character Recognition
A technology that can take written words and convert them back into computer-readable form, provided they're in the right font, using the correct colors sometimes, at the right point size and pitch, dark enough on the paper, and you're prepared to spend several centuries correcting all the 1's that came out as l's, all the O's that came out as 0's, and all the :'s that come out like ;'s.
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