There are many different encryption methods. Each is developed for a particular purpose. Each method employs an algorithm and key to convert raw data to the encrypted form known as ciphertext. Additionally, there are a variety of encryption modes, which determine how the chunks of ciphertext relate to each other.
This is the most basic form of encryption. This method of encryption was employed in email applications and to secure communications during World War II, as shown in the film The Imitation Game. The symmetric algorithm takes an unstructured text message and then jumbles the mathematical permutations. It then encodes the message using the secret key used to encode it. This key is typically only used once and must be kept secure after the message has been decrypted.
Asymmetric and public-key encryption are also kinds of encryption. RSA is the most well-known algorithm for public-key cryptography. Its security is based on the difficulty of calculating large prime numbers. Another common method of Asymmetric encryption is the diffie-hellman protocol, which utilizes the same method to secure a key exchange.
A symmetric method of encryption is the Triple DES technique, which is a method of encrypting data blocks three times with the Data Encryption Standard (DES) Cypher. This method is used to protect ATM PINs as well as UNIX passwords. Triple DES is slow, however it offers excellent security against hackers. Elliptic Curve Cryptography is a more advanced encryption technique that offers better security without requiring a longer set of keys. This technique is utilized in SSL and TLS protocols for web-based communication encryption.