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Cryptology vs Cryptography - Definitions and Differences

By Lane Wagner on Dec 16, 2019

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Many new developers are jumping right into writing code, usually for those fat paychecks, without learning much about the history of Computer Science. Alan Turing is recognized as the father of Computer Science, though many don’t know that his roots were in cryptology and mathematics. It was out of cryptology, cryptography, and mathematics that computer science was born.

What many computer scientists even these days don’t recognize is that cryptography and cryptography are not the same. In fact, many people say cryptography when they really are referring to cryptology or cryptanalysis. Let’s go over the formal definitions of each term, and look at how they compare one to another.


The scientific study of cryptography and cryptanalysis.


Cryptology is the science of secret messages. Anything that has to do with making or breaking codes falls into cryptology’s domain. Cryptology can also be thought of as the study of encryption and decryption.

alan turing

Alan Turing


Cryptography is the practice and study of techniques for secure communication in the presence of third parties called adversaries.


People often lazily use Cryptography in place of the word cryptology, but in reality, cryptography focuses only on creating secure cryptosystems. For example, the design of RSA would have been cryptography work.


You use Cryptanalysis to breach cryptographic security systems and gain access to the contents of encrypted messages, even if the cryptographic key is unknown.


Cryptanalysis is the inverse of cryptography, this is, in contrast, the study of how to break secret codes, not make them. Having a solid understanding of cryptanalysis is fundamental in cryptography however, as one must know their enemy.

Honorable Mention - Cryptocurrency

A cryptocurrency is a digital asset designed to work as a medium of exchange that uses strong cryptography to secure financial transactions, control the creation of additional units, and also verify the transfer of assets.


In the past few years, the slang term “crypto” has been hijacked. It used to mean cryptography or cryptanalysis but has recently come to be understood as cryptocurrency.

Cryptocurrencies such as Bitcoin utilize cryptographic techniques to securely transfer digital assets without a central authority.

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