RSS 2.0, Atom, JSON Feed, OPML, WebSub, and the enclosure tag that accidentally built an industry.
Section 1 of 6 · 8 pieces
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A direct comparison of RSS 2.0 and Atom (RFC 4287) — what each mandates, where they diverge on dates, IDs, and content types, and why both are still in active use.
The Format and Its Plumbing
The story of the RSS enclosure element — Dave Winer's 2001 addition, Adam Curry's early experiments, and how a three-attribute XML tag became the technical foundation for an industry worth billions.
The Format and Its Plumbing
An account of Brent Simmons and Manton Reece's JSON Feed specification — why they wrote it, what it simplifies over XML, and which feed readers adopted it.
The Format and Its Plumbing
OPML as the de-facto portable subscription format — its structure, its adoption across Feedly, NetNewsWire, and Inoreader, and why the absence of a better standard has kept a 2000-era format central to feed readers for two decades.
The Format and Its Plumbing
How WebSub (formerly PubSubHubbub) replaced polling with server-push for feed updates — the hub-subscriber model, Google's original hub, and the W3C standardisation that followed.
The Format and Its Plumbing
Feed autodiscovery via the HTML link element — the two-line convention that lets a reader find a site's feed without the user knowing what a URL is.
The Format and Its Plumbing
An argument piece on why publishers truncate feeds — the traffic and analytics logic, the reader-experience cost, and the platforms that have forced the issue.
The Format and Its Plumbing
The podcast namespace extension project — chapters, transcripts, soundbite, funding, and the value tag — and the tension between an open specification and Apple Podcasts' de-facto control of the directory.