Re: URI and URl

Although the post below is true in practice, there is a technical difference 
that I thought some on the list might like to know (delete this now if you 
don't care about technicalities):

According to the URI Working Group:

A URI can be further classified as a locator, a name, or both.   The term 
"Uniform Resource Locator" (URL) refers to the subset of URI that identify 
resources via a representation of their primary access mechanism (e.g., 
their network "location"), rather than identifying the resource by name or 
by some other attribute(s) of that resource.  The term "Uniform Resource 
Name" (URN) refers to the subset of URI that are required to remain globally 
unique and persistent even when  the resource ceases to exist or becomes 
unavailable.
....
A URN differs from a URL in that it's primary purpose is persistent labeling 
of a resource with an identifier.  That identifier is drawn from one of a 
set of defined namespaces, each of which has its own set name structure and 
assignment procedures.  The "urn" scheme has been reserved to establish the 
requirements for a standardized URN namespace, as defined in "URN Syntax" 
[RFC2141] and its related specifications.

Information obtained at http://www.ics.uci.edu/pub/ietf/uri/rfc2396.txt

More on URNs:

An URN MUST be considered an opaque URL by URL resolvers and passed (with 
the "urn:" tag) to an URN resolver for resolution.  The URN resolver can 
either be an external resolver that the URL resolver knows of, or it can be 
functionality built-in to the URL resolver.

To avoid confusion of users, an URL browser SHOULD display the complete URN 
(including the "urn:" tag) to ensure that there is no confusion between URN 
namespace identifiers and URL scheme identifiers.

Information obtained at ftp://ftp.isi.edu/in-notes/rfc2141.txt

So basically, a URL is a specific type of URI, and conforming browsers are 
supposed to treat it a URN as a URL except that it puts "urn:" in front of 
it.

So any type of URI will be treated as a URL, so Gio is right when he says 
both mean a web address.

Hope nobody was too bored by this.

>Hi ;-) the difference between the two is one has an i and the other has an
>l.
>uri =  uniform resource indicator
>url =  uniform resource locator
>
>Both mean the same thing ....web address ;-)

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