SHA-2 Algorithm

SHA-2 (Secure Hash Algorithm 2) is a family of cryptographic hash functions designed by the United States National Security Agency and first published in 2001, later adopted by NIST as a federal standard. The family includes six variants producing digests of 224, 256, 384 or 512 bits, built on the Merkle-Damgard construction with a Davies-Meyer compression function. SHA-2 was developed as a successor to SHA-1 after weaknesses were found in that earlier algorithm, and it remains secure against all known practical attacks, including those anticipated from quantum computers. It is used throughout TLS and SSL, PGP, SSH and S/MIME, and underlies applications such as Bitcoin transaction verification, Debian package authentication, DNSSEC and Linux password hashing. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/