How Many Versions of RSS Language Standard?

     RSS is relatively new. Many versions have been developed in recent years:

     RSS 0.90 - The earliest known version of RSS released to the public by Netscape in 1999. RSS 0.90 is based on RDF (Resource Description Framework). When RSS 0.90 was created, the RSS initialization stood for Rich Site Summary and not Really Simple Syndication.

RSS 0.91 - Developed by UserLand in 2000.

RSS 1.0 - Published as a proposal by a group led by Rael Dornfest at O'Reilly in 2000.

RSS 2.0 - Released through Harvard under a Creative Commons license in 2003.

What Is Atom?

     Atom is an XML-based document format that describes lists of related information known as "feeds". Feeds are composed of a number of items, known as "entries", each with an extensible set of attached metadata. For example, each entry has a title.

What Are Main Differences between RSS 2.0 and Atom 1.0?

Main differences between Atom 1.0 and RSS 2.0 :

     Atom has separate "summary" and "content" elements, while RSS only has one "description" element.

     Atom standardizes auto-discovery in contrast to the many non-standard variants used with RSS 2.0.

     In Atom, it is mandatory that each entry have a globally unique ID, which is important for reliable updating of entries.

     Atom 1.0 allows standalone Atom Entry documents whereas with RSS 2.0 only full feed documents are supported.

     Atom specifies that dates be in the format described in RFC 3339. The date format in RSS 2.0 was underspecified and has led to many different formats being used.

What Is the Icon for RSS and Atom?

     The Web browser and Website syndication industry has adopted a standard icon to identify syndicated content as shown below :

What RSS 2.0 Files Look Like?

<?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.someexamplerssdomain.com/main.html</link>

        <lastBuildDate>Mon, 06 Sep 2010 00:01:00 +0000 </lastBuildDate>

        <pubDate>Mon, 06 Sep 2009 16:45:00 +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/</link>

                <guid>unique string per item</guid>

                <pubDate>Mon, 06 Sep 2009 16:45:00 +0000 </pubDate>

        </item>

</channel>

</rss>

What Atom 1.0 Files Look Like?

<?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>

                <author>

                      <name>John Doe</name>

                      <email>Kingpeg@example.com</email>

                </author>

        </entry>

</feed>

Including in HTML

     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">

Thanks to dev.fyicenter.com