Salt is a crucial component in modern cryptography techniques, specifically in password security. It is a random value, usually a long string of characters, that is generated and used in conjunction with a plain text password to create a hashed password.
The process of salting involves combining the salt value with the password before hashing it. The resulting salted password is then stored in the database. When a user tries to log in, their entered password is combined with the same salt value and hashed. If the resulting hashed password matches the stored salted password, authentication is successful.
The purpose of using salt is to add an extra layer of security to credentials or sensitive data. By using a unique salt value for each user, even if two users have the same plain text password, their resulting hashed passwords will be different. This prevents attackers from easily identifying common passwords or cracking multiple passwords simultaneously using precomputed tables, such as rainbow tables.
It is important to note that the salt value itself is not considered a secret and can be stored alongside the hashed password. However, to ensure its effectiveness, the salt value must be unique for each user and sufficiently long.