@SFOMuseum Twitter Posts This is SFO Museum's archive of the @SFOMuseum Twitter account.
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During World War II, all sides used mechanical ciphers. The U.S. military’s M-209 portable crypto machine required users to encrypt text one letter at a time. By turning a crank, the scrambled message printed out on paper tape. #MathAtSFO #Math #cryptology #cipher . This tweet was posted on March 28, 2022.