Cryptology is the section of mathematics that deals with both cryptography and cryptoanalysis. Cryptology is the science of both developing techniques to secure information (enciphering) and developing ways of cracking the encrypted code (deciphering).
Normally cryptology is applied to communications but is increasingly applied to the storage of data and information.
Cryptography is used to develop methods to keep messages and information secure by encrypting it. Encryption is a method of converting the data or information from a normal readable format, known as plaintext, into a format that is not readable, known as ciphertext, without being converted back to plaintext.
Cryptoanalysis refers to the practice of analyzing ciphertext with the intent of breaking it. Cryptoanalysis is the study of ways that can be used to obtain plaintext information from encrypted information without using the intended method such as using a key to decrypt the information.