publics

 publics  are the combined set of people who make up the readership or audience of a post. The term comes from literary theory and contrasts the typically assumed 'public' vs 'private' dichotomy.

Author vs commenter publics
There are at least two "publics" of a specific post, heavily overlapping but different: One key difference between these two publics is that commenters may only perceive / expect the direct context of the specific instance of the post, that is they may not consider the audience/readership of syndicated (POSSE) copies, or even the "original" post, if the specific instance is a silo POSSE copy itself.
 * 1) Author-perceived public: The audience/readership that the author of a post perceives, and thus (whether intentionally or not) writes / caters / curates the post according the context of that audience/readership (including indirectly via syndication/POSSE), whether in focus, in details (or omission thereof), or expressiveness (or self-censorship).
 * 2) Commenter-perceived public: When commenting on a post, the commenter perceives a specific audience/readership of the post, which they expect will or are likely to read any comment they write, including the author herself, and especially previous commenters.

In particular, commenters may be assuming only the immediate "public" of the specific post instance, and may not necessarily expect that the broader "publics" of the original post, and other syndicated copies, might see their comment(s), e.g. via backfeed.

Articles
Articles about the concept of "publics" and how it may apply to design of online publishing systems.


 * 2008-04-29 Digital publics, Conversations and Twitter
 * 2009-08-14 How Twitter works in theory

Ben Werdmuller
has posted about this since 2015-05-05:
 * http://werd.io/2015/publish-on-your-own-site-reflect-inwardly

Which is about posting only on your own site (even if publicly), and not POSSEing, to deliberately choose the "public" you're posting too.

See also the comments on that post for similar thoughts from and others.

Tantek
undefined Public "silo" posts vs. public personal site posts.

While over time I have been collapsing my "publics" as I "ownyourdata" more of my types of posts and POSSE to silos I used to post directly to, I find that I still perceive a very different set of viewers/audiences in some silos vs my personal site (and its default POSSE destinations), and thus actually feel a sense of anxiety about switching posting from some silos to my site, or from partial PESOS of some post types to full POSSE.

Examples of publics:
 * tantek.com personal site - who knows how many readers, 1000s of hits per day, auto-POSSEd to Twitter (70k+), manual-POSSEd to Instagram (2.2k+), and previously (til 2018 August) to Facebook and a fraction of 24k+ “followers” that actually see the posts - evidenced by spiking of posts liked by a few early on
 * key: assumed to be broadly personal + professional - in real-time-ish
 * blog posts syndicate to Planet Mozilla - thus I'm likely self-censoring blog posts a bit for that professional context
 * search engines index/show results high - thus strongly affects future professional/personal searchers
 * Instagram - 2.2k+ perceived to be mostly personal contacts plus randoms (anons?) I don't know so I don't feel self-conscious about.
 * more personal things published as IG stories, often to a more frequently than I might on my own site - and that realization (along with recently adding photo support to my site) is making me re-assess/reflect on what I want in a personal site photo posting flow (including what to put in a home page feed vs quietly go into my public archives)
 * questioning whether: do I even want a feed/page of "all recent photos" at all? especially if it would cause me to post fewer things (self-censor more) than I do currently "publicly" on a silo?
 * W3C email lists
 * assumed nearly 100% professional
 * thus only professional posts, and very much self-edited for as professional/minimal as possible
 * Facebook - I don't directly post anything here, however indirectly others post photos of me here, and I might even tag them, thus *implicitly* publishing photos on FB, or at least explicitly taking actions (tagging) which causes those "public" photos to show up on my profile page (thus effectively publishing)
 * 24k+ assumed mostly professional, though high breadth of personal
 * assume most posts not seen by most people due to Facebook's "the algorithm"
 * assume photo posts seen by more people (e.g. NP photos)
 * question: would/should I repost NP photos of me to my own site?

Examples of semi-publics: (e.g. "private" posts to 100s of people who I can't keep track of in my head as a specific list/set, thus I have to treat socially as nearly public, but not to randoms/strangers/future searchers)
 * Foursquare - private yet viewable by 600+ people
 * assumed nearly all personal
 * more personal things published, ok with ephemera that I assume is not indexed by search engines

The "Facebook" Conversation
This seems to be increasing common when ever a camera appears, especially if there are children invovled, as a form of Internet etiquette. Typically it starts with the photographer establishing how they use Facebook etc, what the default sharing settingss are/will be for the post, whether they tag, if the keep it up and where they post etc, before asking other people what they are comfortable with, so a rough consensus emerges (which also gives people an option to opt out of being in the photo).

Identities
Publics can also be compared with Author identities. As an example, most people behave differently with different groups of people based on their familiarity and past experiences. Posting a variety of public and/or private material will likely fall in line with these identities over time. write.as has an interesting discussion of identies on their site.