ENCRYPTION

Encryption is the process of converting plain text or data into a coded message that cannot be understood by unauthorized parties. There are various encryption techniques that are used to achieve this.

1. Symmetric-key encryption: In this technique, a single key is used for both encryption and decryption. This means that the same key used to encrypt the data is also used to decrypt the data. Examples of symmetric-key encryption algorithms include Advanced Encryption Standard (AES) and Data Encryption Standard (DES).
2. Asymmetric-key encryption: Also known as public key encryption, this technique uses two different keys for encryption and decryption. One key is known as the public key, and it is used for encrypting the data, while the other key, known as the private key, is used for decrypting the data. Examples of asymmetric-key encryption algorithms include RSA and Elliptic Curve Cryptography (ECC).
3. Hashing: Hashing is a technique that converts data of any length into a fixed-length string of characters, known as a hash value or message digest. The hash function is a mathematical algorithm that maps the input data to a unique fixed-length output. Hashing is commonly used to ensure data integrity and detect whether the original data has been altered or modified in any way.
   
   Quantum encryption: This technique uses the principles of quantum mechanics to secure data transmission. It involves encoding information in quantum states, which cannot be copied or measured without altering the information. Quantum key distribution is a common example of quantum encryption.
   
   Homomorphic encryption: This technique allows computation on encrypted data without decrypting it first. This means that the data can be processed and analyzed without being exposed to unauthorized parties. Homomorphic encryption is still an emerging technology and is not yet widely used.