lgorithm) A family of popular cryptographic hash algorithms used to create digital signatures and hashes for blockchain transactions. In 1993, the 160-bit SHA was developed by the National Institute of Standards & Technology (NIST).
SHA-1, SHA-2 and SHA-3
SHA-1 was the first SHA revision in 1994. SHA-1 is similar to the MD4 and MD5 algorithms developed by Rivest, but is slightly slower and more secure. See MD5
. Released in 2001, the stronger SHA-2 superseded SHA-1.
SHA-3 was released in 2015, which supports the same hash lengths as SHA-2 but uses a different method based on the Keccak algorithm. SHA-3 was the result of a NIST competition for a new hash standard that began in 2006 and ended in 2012.
SHA-256 and SHA-512
SHA-256 and SHA-512 are SHA-2 algorithms using hash lengths of 256 and 512 bits respectively, and SHA-224 and SHA-384 are truncated versions. SHA-256 is the hash algorithm used in the Bitcoin blockchain. See cryptographic hash function
and digital signature