An acct URI looks like this:
acct:joeblow@example.com
Typically an acct URI is used to turn an e-mail address or
For example, this
@reiver@changelog.ca
Gets turned into this acct URI:
acct:reiver@changelog.ca
The TL;DR of why acct URIs‽ is —
… because people seem to be comfortable with something that looks more like an e-mail address or as username as an identifier but the technology only understands URLs and URIs; so you still have to turn things that look like e-mail address and usernames into URLs and URIs; which is what acct URI is; and “no”, mailto URI won't work;
… because a new URI scheme makes it easy to identify that it should be used with
There are many conceptual places where some kind of an identifier is a core part of it.
For example, on any social protocol I am aware of, there is some type of notion of an identifier.
BBS echo-mail has them. BBS net-mail has them. Internet e-mail has them. Internet finger-protocol has them. Internet gemini-protocol has them. (Multi-User) Linux & Unix operating systems have them. Twitter has them. Etc.
The identifier enables you to send messages, to share photos & images, to control data, etc.
With a single centralized system, dealing with identifiers is comparatively more straight-forward. But when dealing with a distributed, decentralized, or federated system, things can get more complex — for example, how do you point to and interact with someone or something from a different node on the network? Etc.
Experience (with OpenID and other systems) seems to suggest that (at least currently) most people are more comfortable with using something that looks more like an e-mail address or as username as an identifier rather than a URL or a URI. For example —
But
Most users of the Fediverse aren't aware of acct URIs. And really, they don't have to be aware of them!
But behind the scenes, acct URIs are used by
Behind the scenes, a
If you are a programmer / software engineer / software developer / etc, then you may need to be aware of acct URIs, and have some level of understanding of them.
Part of the process of resolving a Fediverse ID transfomrs a Fediverse ID into an
Here is an example of transforming a Fediverse ID into an
at sign ↓ @joeblow@example.com ← Fediverse ID acct:joeblow@example.com ← acct URI ↑ no at sign
A client would then make a request to:
https://example.com/.well-known/host-meta
To discover what the (template) URL for
https://example.com/.well-known/webfinger?resource={uri}
Then make a request to:
https://example.com/.well-known/webfinger?resource=acct:joeblow@example.com
This
For more information on acct URI see: