culminated leibniz 's notion calculus ratiocinator ca cryptographic algorithms first cryptographic algorithm deciphering encrypted code developed al kindi th century arab mathematician ''a manuscript deciphering cryptographic messages'' gave first description cryptanalysis frequency analysis earliest codebreaking algorithm ref name dooley ref mechanical contrivances discrete states ''the clock'' bolter credits invention weight driven clock key invention europe middle ages particular verge escapement provides us tick tock mechanical clock accurate automatic machine
Formal science Computer science Algorithms