Re: The UR* scheme registry, Citing URL/URI specs

Keith Moore (
Fri, 24 Oct 1997 15:17:48 -0400

Message-Id: <>
From: Keith Moore <>
To: Larry Masinter <>
cc: Al Gilman <>, Dan Connolly <>,
Subject: Re: The UR* scheme registry, Citing URL/URI specs 
In-reply-to: Your message of "Fri, 24 Oct 1997 11:46:25 PDT."
Date: Fri, 24 Oct 1997 15:17:48 -0400

This discussion reminds me of the discussion about the use
of the term "charset".  I18N experts want to use different
terms: "character set", "character encoding scheme", and so
forth, because they're very concerned about the differences
between these.  MIME has its own notion of "charset"
which isn't quite either of the above.  Most people can
use terms "charset" or "character set" without needing
or caring about such precision, and without being misunderstood.
(unless they're talking to an expert...)

Note, however that most technical specifications aren't written 
for "most people" ... they're written for experts.  Someone 
implementing HTML may well need to know the difference between 
URLs and URNs -- or at least that URLs aren't the only kind of 

> I think that's a good summary of the situation. HTML and XML
> can say they use URIs, and then point to a W3C note that
> says "A URI is defined by IETF, currently it points to URLs,
> and there is some work on URNs".

This sounds reasonable.
> Here's a puzzle: 
> A URN is a kind of a URL:
>  One way to locate a resource is to name it. Of course,
>  there's some assumption of a mechanism by which names
>  can get looked up and turned into resource locations.
> A URL is a kind of a URN:
>  One way to name a resource is with its location;
>  "the thing that is located at X". It's not a very
>  good name, but then, not all names are good in that role.

While I agree that this is one way to name something,
it doesn't fit with the *definition* of URNs, which
says that they're location-independent.

Again, it doesn't matter to the average Joe, but it does 
matter to an expert.