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Comment by hot_gril | Hacker News Reader

When did "URI" become a thing? Was it not cool enough to call them URLs, so they had to make another abbreviation that looks very similar? I'll bet there's supposed to be a difference, but they're totally used interchangeably.

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1998 [1] although the "URI working group" was active in 1994 describing URNs [2] and URLs [3]. There were also URCs [4] which never took off [5]

[1] https://www.rfc-editor.org/rfc/rfc2396

[2] https://www.rfc-editor.org/rfc/rfc1737

[3] https://www.rfc-editor.org/rfc/rfc1737

[4] https://en.wikipedia.org/wiki/Uniform_Resource_Characteristi...

[5] https://en.wikipedia.org/wiki/Uniform_Resource_Name#URIs,_UR...

The Wikipedia page on URIs has examples that look a lot like URLs. Seems it's trying to say that URLs are only for WWW addresses, but Postgres refers to things like "jdbc:postgresql://host:port/database" as URLs: https://www.postgresql.org/docs/6.4/jdbc19100.htm

Or maybe the presence of host:port qualifies it as a URL.

The only difference between a URI and URL is semantic - URLs point to resources over a network, URIs point to resources that could be anywhere. Colloquially they're used interchangeably.

A URL is a URI.

A URI (indicator) is a unique reference to a resource, of some kind.

One type of URI is a URN (name), e.g. doi:10.5281/ZENODO.31780 - a unique name for a resource, but no instructions on how to obtain it

Another type of URI is a URL (location), e.g. https://doi.org/10.5281/ZENODO.31780 - same resource in this case, but now we know we can obtain it via the HTTPS protocol

Few people call the address in the web browser a "URI" any more, even though technically it is one. Your JDBC URL is a URL, as is "mailto:president@whitehouse.gov" or "tel:+44-118-999-881-999-119-7253"

I get what they were going for here, but ehhh, the only useful designation is URL. And even acknowledging that URIs exist, it's overly broad to refer to http://... as one. I remember seeing "URI" a lot some ObjC libraries to refer to URLs, it was just confusing.

> the only useful designation is URL

Yup, URNs were part of the "semantic web" craze, so you could e.g. record facts about a book with isbn: scheme URNs. Nothing much consequential ever came from all that committee busywork, but people got to pontificate and sound smart talking about reification and so on. I still wonder who paid for all of it.

https://en.wikipedia.org/wiki/Resource_Description_Framework

Seems like URNs fit into the XML/XMPP/SOAP genre, old bloated stuff. For some reason there had to be a whole fad for people to realize you can just shove data into JSON and it's good enough.

I highly recommend reading Weaving the Web by TBL. He explains how URI (identifier) was the term he wanted but he settled on URL (locator) because of politics. The semantics are actually fairly important IMO. Does your URI represent a resource's identity or where that resource is?

It's important that the URL tells you where something is, I agree. For a string that doesn't do that, there's no need for a fancy universal term.

URI came first and URL was adopted for dubious reasons. Personally, I now use URL for user-facing things because more people know what that is, and URI when talking to other developers because it sparks conversations like this which I think are useful.

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