article

An  article  is a kind of post that typically has more structure than a simple note. Articles usually have a name (title), multiple paragraphs, and often subheadings, blockquotes, embedded images, and a footer of references or citations.

How to mark up?
The core difference to a note is that there is a title, marked up as, that's different from the content.

If the article has embedded images or photos, where the photos are intended to be displayed interspersed with the text, then do not add the  class to the images, as that will turn the article into a photo post.

IndieWeb Examples
There are plenty of examples of IndieWeb sites posting articles, as articles essentially represent what used to simply be called "blog posts".

gRegor Morrill
has been publishing articles using Nucleus since 2002-01-26:
 * http://gregorlove.com/2002/01/1/
 * At the time, I treated my site more like a journal and the design did not use titles for each post. In later years, I added default titles for entries missing them.

Tantek
undefined has been explicitly posting articles using Falcon on tantek.com since 2010-08-19, and before that with monthly static files and fragement ID permalinks since 2002-08-08:
 * 2010-08-19: Bringing Back The Blog
 * 2002-08-08: Web standards and bird brains

Aaron Parecki
has been publishing articles using p3k on aaronparecki.com since 2004-12-03
 * http://aaronparecki.com/articles
 * http://aaronparecki.com/articles/2004/12/03/1/german-radio-program

Barnaby Walters
has been publishing articles using Taproot (or some similar predecessor) since at least 2010-10-02
 * http://waterpigs.co.uk/articles/
 * RCX on OS X is the earliest content I’ve imported so far

Kartik Prabhu
has been explicitly posting articles using Bundle on kartikprabhu.com since 2013-06-01:
 * First article on own domain: Invictus
 * Imported old articles from Blogger going back to 2006-10-23 2006 articles

David Shanske
has been publishing articles using WordPress since 2009-09-20 (link?) on his own domain
 * Had previously and concurrently blogged on a variety of domains about various topics

Jonny Barnes
has been posting articles on his blog since 2007-07-19

Kimberly Hirsh
has been publishing articles using Micro.blog since 2020-01-06.
 * She posted articles in WordPress beginning 2009-02-26.
 * She previously published blog posts on other domains and across other hosted blogs.
 * She imported LiveJournal posts going back to 2007-03-01.
 * She intends to import all of her findable writing from across the Internet, which goes back to 2001-03-15, but her earliest blog posts might be considered long notes rather than articles.

Max Dietrich
has been publishing articles using Strapi since ~ 2018.
 * He first posted articles using WordPress and after some trying around decided to migrrate all articles to Strapi.
 * http://mxd.codes/articles

ID markup for paragraphs etc
Marking up paragraphs with unique id attributes may enable more granular referencing for quotations within them, and possibly more granular comments as well.

Blogger
Blogger introduced "titles" to blog posts in 1999? E.g.
 * has https://epeus.blogspot.com

Facebook
In 2015 Facebook revamped its "Notes" feature to basically support Medium-like articles with titles, and minor style-editing.
 * 2015-08-17
 * http://thenextweb.com/facebook/2015/08/17/through-the-medium-of-facebook/
 * https://twitter.com/davewiner/status/633244015098507264
 * apparently Facebook hired the principals of the design studio that designed Medium: https://twitter.com/Fahrni/status/633287361409867776
 * 2015-09-25 http://www.theverge.com/2015/9/25/9398895/facebook-notes-redesign
 * 2015-10-09 https://blog.hootsuite.com/the-good-the-bad-and-the-ugly-medium-vs-facebook-notes/

POSSE Examples: (screenshots needed - Tantek has some he should get around to uploading)
 * https://www.facebook.com/notes/tantek-çelik/embrace-joy-in-the-present/10153683368072912
 * original: http://tantek.com/2016/074/b1/embrace-joy-present

Medium
Medium supports articles with a header image, a name, and minor style-editor.