News

web feed On the World Wide Web, a web feed (or news feed) is a data format used for providing users with frequently updated content.

Content distributors syndicate a web feed, thereby allowing users to subscribe a channel to it by adding the feed resource address to a news aggregator client (also called a feed reader or a news reader).

Users typically subscribe to a feed by manually entering the URL of a feed or clicking a link in a web browser or by dragging the link from the web browser to the aggregator, thus “RSS and Atom files provide news updates from a website in a simple form for your computer.”

RSS

RSS (RDF Site Summary or Really Simple Syndication) is a web feed that allows users and applications to access updates to websites in a standardized, computer-readable format.

Subscribing to a website RSS removes the need for the user to manually check the website for new content. Instead, their browser constantly monitors the site and informs the user of any updates. The browser can also be commanded to automatically download the new data for the user.

RSS feed data is presented to users using software called a news aggregator. This aggregator can be built into a website, installed on a desktop computer, or installed on a mobile device. Users subscribe to feeds either by entering a feed’s URI into the reader or by clicking on the browser’s feed icon. The RSS reader checks the user’s feeds regularly for new information and can automatically download it, if that function is enabled. The reader also provides a user interface.

An example feed could have contents such as the following:

<?xml version="1.0" encoding="UTF-8" ?>
<rss version="2.0">
  <channel>
    <title>RSS Title</title>
    <description>This is an example of an RSS feed</description>
    <link>http://www.example.com/main.html</link>
    <lastBuildDate>Mon, 06 Sep 2010 00:01:00 +0000 </lastBuildDate>
    <pubDate>Sun, 06 Sep 2009 16:20:00 +0000</pubDate>
    <ttl>1800</ttl>

    <item>
      <title>Example entry</title>
      <description>Here is some text containing an interesting description.</description>
      <link>http://www.example.com/blog/post/1</link>
      <guid isPermaLink="false">7bd204c6-1655-4c27-aeee-53f933c5395f</guid>
      <pubDate>Sun, 06 Sep 2009 16:20:00 +0000</pubDate>
    </item>

  </channel>
</rss>

Atom

Atom applies to a pair of related Web standards. The Atom Syndication Format is an XML language used for web feeds, while the Atom Publishing Protocol (AtomPub or APP) is a simple HTTP-based protocol for creating and updating web resources.

An example of a document in the Atom Syndication Format:

<?xml version="1.0" encoding="utf-8"?>

<feed xmlns="http://www.w3.org/2005/Atom">

  <title>Example Feed</title>
  <subtitle>A subtitle.</subtitle>
  <link href="http://example.org/feed/" rel="self" />
  <link href="http://example.org/" />
  <id>urn:uuid:60a76c80-d399-11d9-b91C-0003939e0af6</id>
  <updated>2003-12-13T18:30:02Z</updated>
  
  
  <entry>
    <title>Atom-Powered Robots Run Amok</title>
    <link href="http://example.org/2003/12/13/atom03" />
    <link rel="alternate" type="text/html" href="http://example.org/2003/12/13/atom03.html"/>
    <link rel="edit" href="http://example.org/2003/12/13/atom03/edit"/>
    <id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
    <updated>2003-12-13T18:30:02Z</updated>
    <summary>Some text.</summary>
    <content type="xhtml">
      <div xmlns="http://www.w3.org/1999/xhtml">
        <p>This is the entry content.</p>
      </div>
    </content>
    <author>
      <name>John Doe</name>
      <email>johndoe@example.com</email>
    </author>
  </entry>

</feed>

The following tag should be placed into the head of an HTML document to provide a link to an Atom feed.

<link href="atom.xml" type="application/atom+xml" rel="alternate" title="Sitewide Atom feed" />

RSS compared with Atom

RSS 2.0 Atom 1.0
author author*
category category
channel feed
copyright rights
subtitle
description* summary and/or content
generator generator
guid id*
image logo
item entry
lastBuildDate (in channel) updated*
link* link*
managingEditor author or contributor
pubDate published (subelement of entry)
title* title*
ttl

News aggregator

News aggregator, also termed a feed aggregator, feed reader, news reader, RSS reader or simply an aggregator, is client software or a web application that aggregates syndicated web content such as online newspapers, blogs, podcasts, and video blogs (vlogs) in one location for easy viewing. The updates distributed may include journal tables of contents, podcasts, videos, and news items.

Json Feed is a Web feed file format for Web syndication in JSON instead of XML as used by RSS and Atom.