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.