Atom v/s RSS

Hi friends,

  to follow's  our favorite blogs or websites, usually we subscribe Atom or RSS feed  provided by those blogs or  websites. so one should  know the difference  and similarity between them

Similarity

1.   Atom 1.0 and  RSS 2.0 both are used to  published  blogs or website  updates to their subscriber
2.   They are commonly called as  feed or web feed or channel which used by website to inform their subscriber about websites updated content.
3.  Both have their  own specified xml format

Atom 1.0	RSS 2.0
Atom full name is  Atom Syndication Format	RSS means  Really Simple Syndication of  web feed
Atom has 2 variants and it  news feed format design as compare to  RSS	RSS  has 9 variants and it is  older  feed format
Atom is a relatively recent spec and is much more robust and feature-rich than RSS.	RSS 2.0 has the widest acceptance of any feed format but also has significant downfalls.
Atom has one standardized publishing protocols	RSS has two  publishing protocols
Atom has restrictive approaches to validate content data	RSS has a more loose approach to validate content data
Atom provides a mechanism to explicitly and unambiguously define the type of content being provided by the entry, and allows for a broad variety of payload types including plain text, escaped html, xhtml, xml, Base64-encoded binary, and references to external content such as documents, video, audio streams, and so forth.	RSS takes escaped HTML or plain text in their data publishing
Atom web feed specification  used working group instead of  timestamps formatted according to the rules specified by RFC 3339	RSS 2.0 specification relies on the use of RFC 822 formatted timestamps to communicate information about when items in the feed were created and last   updated
Atom uses the standard xml:lang attribute to make it possible to specify a language context for every piece of human readable content in the feed	RSS vocabulary has a mechanism to indicate a human language for the feed, there is no way to specify a language for individual items or text elements.
File format  .atom or .xml	.rss or .xml

RSS  2.0 sample xml code

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

<rss version="2.0">

<channel>

        <title>my feed Title</title>

        <description>this is my test feed description</description>

        <link>http://www.divyangpanchasara.com/main.html</link>

        <lastBuildDate>Mon, 27 Jul 2011 00:01:00 +0000 </lastBuildDate>

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

        <item>

                <title>My Test entry</title>

                <description>Here is some text containing an interesting description.</description>

                <link>http://www.hitechito.com/</link>

                <guid>unique string per item</guid>

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

        </item>

</channel>

</rss>

Atom 1.0  sample xml code

<?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://divyangpanchasara.com/feed/" rel="self" />

        <link href="http://divyangpanchasara.com/" />

        <id>urn:uuid:63ab6c80-d399-11d9-b91C-0003939e0af6</id>

        <updated>2011-06-27T18:30:02Z</updated>

        <author>

                <name>Divyang Panchasara</name>

                <email>divyang@divyangpanchasara.com</email>

        </author>

        <entry>

                <title>Atom-Powered Robots Run in silver-light</title>

                <link href="http://divyangpanchasara/2011/06/27/atom03" />

                <link rel="alternate" type="text/html" href="http://divyangpanchasara/2011/06/27/atom03.html"/>

                <link rel="edit" href="http://divyangpanchasara/2011/06/27/atom03/edit"/>

                <id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>

                <updated>2011-06-27T18:30:02Z</updated>

                <summary>Some text.</summary>

        </entry>

</feed>