A deep link is any URI that includes a string "after the /", as in "en.wikipedia.org/wiki/deep_linking".

permalinks

In the context of a blog, these are called permalinks. According to Tom Coates "it was effectively the device that turned weblogs from an ease-of-publishing phenomenon into a conversational mess of overlapping communities. For the first time it became relatively easy to gesture directly at a highly specific post on someone else's site and talk about it. Discussion emerged. Chat emerged. And - as a result - friendships emerged or became more entrenched. The permalink was the first - and most successful - attempt to build bridges between weblogs. It existed way before Trackback and I think it's been more fundamental to our development as a culture than comments... Not only that, it added history to weblogs as well - before you'd link to a site's front page if you wanted to reference something they were talking about - that link would become worthless within days, but that didn't matter because your own content was equally disposable. The creation of the permalink built-in memory - links that worked and remained consistent over time, conversations that could be archived and retraced later."

In other words, these were the very basis of web 2.0.

use

Encouraging the typein of deep links or simple domain names is sometimes called "direct navigation". This is done by ensuring that information remains at a stable URI, fixed URI, reliable URI, known URI, stable web address, fixed web address, reliable web address, or known web address:

A hotlink is a form of deep link that does not necessarily involve relying on the web host publishing it to present it, e.g. just an image is used.
This can be controversial.

value

confidence

Only a URI that remains stable over a long period of time that it can be confidently and reliably link?ed, is likely to be relied upon as a trusted source of information.

Extreme stability is the most important aspect of any solution to the URL and 404 problem that plagues the World Wide Web and makes the public not trust online information.

certainty

A genuinely persistent identifier assigns documents permanent online addresses such as "openpolitics.ca/abortion" or "cbc.ca/greatest" and "cbc.ca/fifth". No matter how many changes the publisher makes to its IT architecture, documents with persistent identifiers will always be accessible through the same address. A Green URI for instance is an effort by Global Greens? to remain persistent. See URL and 404 problem for a general discussion of the strategy.

recognition

Use of persistent identifiers requires strict adherence to naming conventions but pays off because supporting persistent deep links is the standard way to build recognition of a domain name? and its association with certain subject matter, which aids branding: association of the word with the subject matter as presented by the domain.

credibility in publication

Any published URI must be at least a stable URI, preferably a truly persistent one. However, stupidity - and only that - cause many organizations to fail to meet this constraint, causing their webs to be far less credible. Those that succeed at it, e.g. amazon.com?, use ISBN? or other keys that are associated with the content at the address, and have benefitted immensely from never changing these addresses.

recall

There are further advantages to a human-memorable URI or human-memorable web address such as "cbc.ca/fifth" or "gpo.ca/policy": it can be recalled easily and cited without any search or lookup, as a source, by anyone inclined to believe in the content published at it, e.g. on a call-in radio? show. If the content is maintained by some predictable process - and if moved found without manual effort by redirect - then there's no need to check if it is still active: something useful and valuable will be found "there": just more certainty.

examples

GFDL corpus articles

Wikipedia's standard wiki URIs and the GFDL corpus namespace are key to the move to stable URIs, as that project has put a name on practically everything there is, and maintains stable if not wholly persistent identifiers in many languages, linking from articles in one language to parallel articles in all others. This makes it easy to translate?.

open politics issues

The Imagine Halifax terms and the list of all issues used at openpolitics.ca itself to ensure that issue statements are easy to find and annotate, are two steps towards such a broad standard for open politics itself.

Green policy names

The Green URI was an attempt to build a fixed and stable URI scheme, publish a list of Green URIs and work to persistent identifiers eventually.

The GPO policy book and Green Party of Canada Living Platform were also examples of stable URIs once upon a time. Both appear not to be, now. Given these failures, further attempts to set naming conventions for international Green Party policy likely will await a simultaneous policy wiki for Global Greens?.