The process of becoming a fully approved FIPS is fairly arduous and time-consuming, so it is often useful to reference draft FIPS or draft revisions of FIPS. Further information on the approval process for FIPS is available through
FIPS are numbered. A revision causes the addition of a hyphen and revision number. For example, FIPS 186 is the Digital Signature Standard; after two revisions, its latest version is [FIPS 186-2], which replaces all previous versions. (DSS/DSA is still commonly used to refer to the original U.S. government-devised signature algorithm, although later versions of FIPS 186 have added other signature algorithms, thus permitting their use by U.S. government agencies without a waiver or exception.)
Because of the legal effect of FIPS on U.S. government agencies, FIPS that no longer warrant presumptive government adherence are "withdrawn." Such FIPS may still provide useful information and may still be available from NIST.