What is RSS? An introduction to web feeds

Learn what RSS and other web feeds are, how feed readers work, and where to find feeds for the sites you follow.

A web feed is a small file that a website publishes alongside its pages. It lists the site’s newest articles, each with a link and usually a title, a date, and a summary. RSS is the oldest and best-known feed format, so “RSS” often stands in for web feeds in general.

If you listen to podcasts, you already use feeds. Every podcast is an RSS feed. A podcast app checks each show’s feed for new episodes, and a feed reader does the same for websites.

How a feed reader works

You give a feed reader the addresses of the feeds you want to follow. The app checks each one on a schedule and gathers anything new into a single list. You read in one place instead of visiting each site in turn.

Everything in that list comes from sites you chose, in an order you control. Advertising and low-value posts still exist on the open web, and Den includes tools to reduce junk and sort articles by relevance.

Publishers benefit too. A feed reaches subscribers directly, costs nothing beyond hosting the file, and works with whichever reader a person prefers. The only thing a publisher sees is a request for the file, the same as a browser requesting a page.

Local readers and hosted services

Feed readers come in three kinds.

A local reader runs on your device and connects directly to publishers’ websites. Den is a local reader. Your subscriptions and reading history stay on your devices and in your own iCloud account, and nothing passes through a server operated by the developer. Think of it as a web browser with features for organizing sites and keeping up with what is new.

A hosted service checks feeds from its own servers and delivers the results to its apps and website. Because the servers are always on, a hosted service keeps a continuous archive even while every one of your devices is off, and it works from any web browser. In exchange, your subscriptions and reading history live with the service.

Self-hosted software offers the same always-on behavior on a server you run yourself.

Where to find feeds

Most sites that publish regularly have a feed. The quickest way to find one is to give Den the site’s address. When you add a channel, Den checks the site for feeds and lets you choose.

More ways to grow your library:

• Look for a feed link. Many sites link their feed in the footer or sidebar, often with the orange RSS icon. Opening an RSS link on a device with Den installed fills in the address for you.
• Use the Safari extension. Den’s Safari extension shows the feeds available on the page you are viewing, so you can subscribe while you browse.
• Explore by interest. Explore Feeds in Den suggests sites for the interests you enter. It uses Apple Intelligence through Apple’s Private Cloud Compute, and availability varies by language and region. See Apple’s requirements and Den’s privacy policy for details.
• Import an OPML file. OPML is the standard file for exchanging subscription lists. Export one from another reader and import it into Den to bring your library along. Blogrolls and curated reading lists are sometimes shared as OPML too.
• Follow the trail. Blogrolls, link posts, and the sources your favorite writers cite lead to new publishers on an ongoing basis.
• Ask an assistant, then verify. Chat assistants can propose feeds for a topic, but they sometimes invent addresses. Add each suggestion in Den to confirm it works before relying on the list.

Each platform guide walks through these steps in detail: Mac, iPad, and iPhone.

Feed formats

Three formats are in common use. Den reads all of them, and when a site offers a choice, any of them will do.

RSS, short for Really Simple Syndication, dates to 1999 and remains the most widely published format. It is based on XML, and extensions add fields for specific kinds of content. Podcast feeds are RSS with extra tags for audio episodes.

Atom arrived in 2005 as an internet standard. It is also XML, with stricter rules: every entry carries a unique identifier and a timestamp, and text is labeled as plain or HTML. Many blogging platforms publish Atom.

JSON Feed was introduced in 2017. It carries the same information as RSS and Atom in JSON, a format that nearly every programming language and web framework handles natively, so it is easy for publishers to produce. A JSON Feed is short enough to read in full:

{
    "version": "https://jsonfeed.org/version/1.1",
    "title": "Example Blog",
    "home_page_url": "https://example.com/",
    "feed_url": "https://example.com/feed.json",
    "items": [
        {
            "id": "https://example.com/2026/11/hello-feeds/",
            "url": "https://example.com/2026/11/hello-feeds/",
            "title": "Hello, feeds",
            "date_published": "2026-11-09T09:00:00Z",
            "summary": "A first post."
        }
    ]
}

Further reading

• About Feeds, Matt Webb’s independent getting-started guide to feeds and newsreaders.
• RSS 2.0 Specification, maintained by the RSS Advisory Board.
• The Atom Syndication Format, RFC 4287.
• JSON Feed Version 1.1.
• OPML 2.0 Specification, the subscription list format. Den OPML describes the attributes Den adds to preserve channel settings.
• Identify Den on your network, for what Den connects to and how publishers can recognize it in server logs.