Wait, the original claim was:

> Email is not part of the web

That's "email", not "emails". I understood that to mean email the concept / technology, not "emails" as in individual email resources.

By that reading, yes, email is on the web. You can link to a mailbox with the mailto: URI scheme.

If you read it as "Individual emails are not on the web" instead, then webmail seems to cover that.

That’s good news for books ("urn:isbn:"), movies ("urn:isan:"), UUIDs ("urn:uuid:"), and so many other things that I thought weren’t on the web.

If I reside in "urn:oid:2.16.840" and I read "https://news.ycombinator.com", is that what they call the inner-platform effect?

I'm guessing the point you're driving at is "these things obviously aren't on the web, so this is wrong"?

The web is an abstract information space that can contain arbitrary links between objects. The web isn't something you load in a browser, it's a way of organising links between things. So, yes, you can link to books, movies, etc. Anything with a URI.

You might be interested in this early document about the World-Wide Web:

https://www.w3.org/People/Berners-Lee/1996/ppf.html

It describes what I'm saying in more detail, including explicitly mentioning books as something that can be addressed in URI space.

If the definition of the web is "anything addressable via URI," then the definition of the web is no longer useful. I can imagine a URN scheme for every atom in the universe. Welcome to the web -- you're soaking in it!

More seriously, I think that -- if pressed -- I'd say that the identifiers are on the web, but the things are not. Other than that, I believe we would agree???

That said, the origin of this discussion is in relation to Google's launching of AMP for e-mail. The justification was that e-mails are on the web, so it's OK to use AMP to push them forward. A better viewpoint, though one I disagree with, relates AMP to being a better mode of HTML. (As opposed to one of the Web.)

Every email message has a unique identifier called the Message-Id, but SMTP does not host messages with an HTTP URI.

Serving public URIs for messages must be done by separate web servers like a webmail client, or a mail archiving tool such as Pipermail.

> an HTTP URI

Note that there's no requirement for something to be an HTTP URI specifically. Any URI will do.

Yet still, without a webmail client (a client that specifically takes an offline protocol and puts it on the “web”) email would not have a URI. You an “link” to a mailbox, but not create a particular mail with a particular identifier then later retrieve it with that same URI. The URI identifies the users mailbox, NOT their mail.

Good point, there are URIs for other protocols (like FTP, Gopher etc).