The draft Federal Information Processing Standard (FIPS)180-4 is a proposed revision of FIPS 180-3. Draft FIPS 180-4 adds a general procedure for creating an initialization hash value and two additional secure hash algorithms: SHA-512/224 and SHA-512/256, and removes a requirement that padding must be done before hash computation begins. SHA-512/224 and SHA-512/256 may be more efficient alternatives to SHA-224 and SHA-256, respectively, on platforms that are optimized for 64-bit operations. Removing the restriction on the padding operation in the secure hash algorithms will potentially create more flexibility and efficiency in implementing the secure hash algorithms in many computer network applications.
The Federal Register Notice (FRN) of this publication is located http://csrc.nist.gov/publications/drafts/fips180-4/FRN_Draft-FIPS180-4.pdf" target="_blank">here (PDF).

Examples of the implementation of the secure hash algorithms SHA-1, SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224 and SHA-512/256, can be found at http://www.nist.gov/CryptoToolkitExamples" target="_blank">http://www.nist.gov/CryptoToolkitExamples.