How Your Printer Spies On You

A lot of color laser printers secretly print codes on every page that help the printer be recognized. The tech was originally supposed to help law enforcement track down criminals forensically- klike ransom notes, counterfeit money, that sort of thing. These tracking dots are usually only visible under LED or UV light, or if you scan in the document and crank up the contrast and saturation to an extreme. When I tested it out myself, I found a pattern of tiny red squares embedded in the text. I’m not sure if that was just an artifact from my scanner or an evolution of the code!