The reason we speak of several standards and not THE standard, is that there is not one standard that specifies everything unambigiously. In fact, there is no standard yet. When there is one, there are things that are not covered by the standard, they are unspecified. These gaps may be filled by later standards. At this point in time, there is no standard at all.
Further information is in the help section.
If you're new here, that's a good place to start. It also contains informations about writing proposals in general and why it is so important to have standards. 10 Feb 2001 Added Search String forum. 9 Feb 2001 Added Remote Caching forum. Posted Example Protocol proposal to Evaluate.