Classical Cryptography is the name given to the ciphers used through history before computers became commonplace. These ciphers are commonly called “pen and paper” ciphers because they were targeting the complexity to be performed by a normal person with only a pen and some paper.

Common classical ciphers include

  • Caesar cipher
  • Vigenere cipher
  • Substitution cipher
  • Transposition cipher
  • Bifid and trifid ciphers

As being resistant to computers was not a goal, all of the classical ciphers provide almost no security today.