What is Cryptography:
Cryptography is, in general terms, the art and technique of creating messages encoded with procedures or secret keys so that it cannot be decrypted except by the person to whom it is addressed or who holds the key.
The word, as such, is formed from the Greek term κρυπτός (kryptós), which means 'hidden', and -graphy, a suffix that means 'writing'.
The objective of cryptography is, therefore, to protect the information sent, so that only the recipient or the people who have the key, can read the message correctly. For this, encryption systems are designed that are only known to authorized persons.
Cryptography was born in antiquity, as a consequence of wars, due to the need that the opposing factions had that their messages could not be read or deciphered by their enemies. Hence, then, they created codes or keys for it.
The discipline that is responsible for the study and research of encryption techniques is called cryptology. For their part, it is the cryptographers who deal with the research and development of encryption techniques based on the use of mathematics. While cryptanalysis is dedicated to the study of cryptographic systems in order to violate them.
In modern times, cryptography has evolved considerably when applied to computing in order to safeguard the security of communications and information shared mainly through the Internet.