Hashing Function: An algorithm that maps data of any size to a fixed size. The output, or hash, is a string of characters that represents the input data. In security, hash functions are used for a variety of purposes, including data integrity checks, password storage, and digital signatures. A secure hash function has the property that it’s computationally infeasible to derive the original input from its hash, making it useful for storing sensitive information like passwords in a form that prevents their recovery even if the hash is known.