Comments on: URI vs. URL: What’s the Difference?

By: Josh

Josh — Tue, 01 Sep 2009 16:13:31 +0000

All URL’s are URI’s. URI’s are more general and include relative addresses. It is incorrect to say “relative URL” because there is no such thing. A URL must include protocol(http, http://ftp...), host name or IP, and a path to the resource. A URI can be any absolute or relative path.

URL: http://www.lonedogpoems.com
URL: http://www.lonedogpoems.com/index.php
not URL: index.php
not URL: ..
The last two are not URL’s but they are still URI’s.

By: Ryan

Ryan — Mon, 24 Aug 2009 13:41:47 +0000

@Jordan Tucker
To clarify further: the presence of a query string does not distinguish a URL from a URI. The key difference are between URL and URN, where a URL declares a unique location from the content can be retrieved where a s URN is merely a name. However, BOTH schemes are considered URIs.

@Seeker
You are a 100% correct: URL and URNs are specialisations of a URI.

This conversation gets a lot more fun when you starting thinking about IRIs

Ryan-

By: Seeker

Seeker — Fri, 21 Aug 2009 10:11:42 +0000

@Giacomo Masetti Both of them are URLs. URL to URI is like a square to rectangle - every square is a rectangle, but only specyfic rectangles are squares.

By: Seeker

Seeker — Fri, 21 Aug 2009 10:08:17 +0000

If you need some examples of URNs there is plenty of them on Wikipedia:
http://en.wikipedia.org/wiki/Uniform_Resource_Name#Examples

Anyone interested should also look at:
http://en.wikipedia.org/wiki/URI_scheme
http://en.wikipedia.org/wiki/URI

By: Ryan

Ryan — Mon, 15 Jun 2009 11:16:50 +0000

Jordan Tucker :
However, this has changed so that a URN is a URI that has the “urn” scheme, and a URL is an abstract term that describes a URI that identifies a resource by its location. Therefore, URLs and URNs are both URIs.

URI is an abstract concept, URL and URN are concrete implementations of a URI.

By: Jordan Tucker

Jordan Tucker — Wed, 10 Jun 2009 23:13:24 +0000

@Giacomo Masetti "http://www.domain.tld/somepath/file.php?mykey=somevalue" is a URI. It's also a URL because it identifies a resource by its location. "http://www.domain.tld/somepath/file.php" is also a URL and a URI. The difference between the two URIs is that the second lacks a query string.

By: Jordan Tucker

Jordan Tucker — Wed, 10 Jun 2009 23:10:50 +0000

Classically, URIs were grouped into two subclasses: a location (URL) or a name (URN). Each scheme was put into one of these subclasses; http into the URL subclass, isbn into the URN subclass.

However, this has changed so that a URN is a URI that has the “urn” scheme, and a URL is an abstract term that describes a URI that identifies a resource by its location. Therefore, URLs and URNs are both URIs.

There’s nothing wrong with using the term URL so long as you know that URL and URI are not interchangeable.

By: Ryan

Ryan — Wed, 20 May 2009 22:36:33 +0000

You can say that they are both a URI and a URL. Again, a URL is basically a sub-class of URI.

By: Giacomo Masetti

Giacomo Masetti — Wed, 20 May 2009 12:08:39 +0000

Can we say that:

“http://www.domain.tld/somepath/file.php?mykey=somevalue”

is an URI

and that the “http://www.domain.tld/somepath/file.php” part is an URL?

By: Reality Me » URL Shorteners Causing a Stir

Reality Me » URL Shorteners Causing a Stir — Mon, 06 Apr 2009 16:13:13 +0000

[...] A URL is a subset of a URI. There is some debate about whether URL has be deprecated or not. See Yuri not [...]