SHA-1 generator

The Secure Hash Algorithm (SHA1) is a widely used cryptographic hash function that generates a 160-bit (20-byte) hash value from any character string. This is used to calculate a test value that is unambiguous according to normal judgment for any digital data (messages) with a maximum length of 264 − 1 bit (≈ 2 exbibytes) and is the basis for creating a digital signature. SHA1 was developed in 1993 by the National Institute of Standards and Technology (NIST) in cooperation with the National Security Agency (NSA). The structure of SHA-1 (originally SHA-0) is similar to the algorithm developed by Ronald L. Rivest, who developed Message-Digest Algorithm 5 (MD5) in 1991.