Encryption

Encryption is simply defined as the method through which plaintext data is converted into ciphertext. The ciphertext can be converted back to the plaintext by an entity that has a decryption key. Encryption is not a new technique and its use goes deep in history. Over several centuries, encryption has been used by humans to protect sensitive information, such as trade secrets and communication between leaders. However, encryption in medieval times was fairly simple and was somewhat easy to crack. Methods, such as transposition or substitution of characters were used. However, as technology advanced, encryption became more automated and machines could encrypt and decrypt messages better than humans.

Early encryption methods

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