conformance, compliance and compatibility

[Esben Stien <executiv@online.no>]

I remember to have read that ISO has standardized on using
conformance for everything that is conforming to a specific
standard but I can't find it again. Anyone know where I could
look?

AFAIK, this is my understanding of these words

Conformance has a deep root different meaning than compliance,
but today that difference is not clear. However, ISO has
standardized on using the word conformance and not compliance
when saying something conforms to a standard. 

Compatibility is for hardware. You can say that a specific
piece of hardware is compatible with another piece of hardware
cause it speaks the same protocol. Compatibility is a way of
saying that two components uses the same interfaces. 

You can not call a system unix today, cause unix today is a
standard. The last unix was sysv. You can however say a system
is conforming to unix (iso posix unix)(ieee 1003.1), so it is a
unix conformant system. (to be technically correct). 

Is there any document that clarifies these words better. I'm
looking for some official documentation from a standards body
like ISO, IEC etc. 

I also see the words comformance and compliance used
interchangably in RFC's,  but to my knowledge I think I remember
that RFC's where also supposed to be using conformance 

-- 
b0ef