Cryptography is the art of creating and using cryptosystems. Cryptanalysis is the art of breaking cryptosystems breaking the code or seeing through the disguise. Cryptology is the study of both cryptography and cryptanalysis. An original message is called plain text. The disguised message is called cipher text.
Encryption refers to any procedure to convert plain text into cipher text.
Decryption refers to any procedure to convert cipher text into plain text. The intended individual who is supposed to be able to see through the disguise is called a recipient. All others are considered opponents, interlopers, eavesdroppers, or third parties. When files are secure, encryption techniques ensure that data stored in a computer cannot be read or compromised. Most security measures involve data encryption and passwords.