Syndication models are various methods of syndicating or crossposting content from one site to another generally based on the source and target of the original post and the copy (or multiple copies) as well as who owns the original version first.
Since the early days of social media the concept of syndicating (or sometimes more commonly, crossposting) content from one service to another was a common pattern to increase the reach and discoverability of content online.
Most indieweb publishing flows include a step involving third party services.
Reasons this is important
- Proliferates your content/links to your content across the web
- Allows people who do not yet have an indieweb presence to catch up with your content
- POSSE: the preferred model, where content is stored under your domain before being pushed elsewhere
- PESOS: an alternative model, where content is posted to 3rd party services before being archived under your domain
- PESETAS: an even poorer model, where content is posted to 3rd party services, and aggregated/shared onto a single other silo (rather than your own domain).
A fuller list of models is delineated at cross-posting.