Method of Encryption

Introduction
The basic function of encryption is essentially to translate normal text into ciphertext. Encryption can help ensure that data doesn’t get read by the wrong people, but can also ensure that data isn’t altered in transit, and verify the identity of the sender.

There are three different basic encryption methods:

 * Hashing: fixed-length signature. Once data is encrypted using hashing, it cannot be reversed or deciphered. Hashing is useful for proving data hasn’t been tampered with.


 * Symmetric methods: also, known as private-key cryptography. Using this method, a sender encrypts the data with one key, sends the data (the ciphertext) and then the receiver uses the key to decrypt the data.


 * Asymmetric methods: or public-key cryptography. It uses two keys for encryption or decryption (it has the potential to be more secure as such). With this method, a public key is freely available to everyone and is used to encrypt messages, and a different, private key is used by the recipient to decrypt messages.

Some examples:
Triple DES was the recommended standard and the most widely used symmetric algorithm in the industry.
 * Triple DES

Triple DES uses three individual keys with 56 bits each.

Triple DES manages to make a dependable hardware encryption solution for financial services and other industries. RSA is a public-key encryption algorithm and the standard for encrypting data sent over the internet. It also happens to be one of the methods used in our PGP and GPG programs.
 * RSA

RSA is considered an asymmetric algorithm due to its use of a pair of keys. You’ve got your public key, which is what we use to encrypt our message, and a private key to decrypt it. Blowfish uses symmetric cipher splits messages into blocks of 64 bits and encrypts them individually.
 *  Blowfish

Tremendous speed and overall effectiveness as many claim that it has never been defeated.

Free availability in the public domain.

Blowfish can be found in software categories ranging from e-commerce platforms for securing payments to password management tools.

It’s the more flexible encryption methods available. Keys used in this algorithm may be up to 256 bits in length and as a symmetric technique, only one key is needed.
 * Twofish

Twofish is regarded as one of the fastest of its kind, and ideal for use in both hardware and software environments.

Freely available.

You’ll find it bundled in encryption programs such as PhotoEncrypt, GPG, and the popular open source software TrueCrypt. The Advanced Encryption Standard (AES) is the algorithm trusted as the standard by the U.S. Government and numerous organizations.
 * AES

Although it is extremely efficient in 128-bit form, AES also uses keys of 192 and 256 bits for heavy duty encryption purposes.

AES is largely considered impervious to all attacks, with the exception of brute force.

Source
http://datashieldcorp.com/2013/06/04/3-different-data-encryption-methods/ http://www.storagecraft.com/blog/5-common-encryption-algorithms/