From http://www.w3schools.com (Copyright Refsnes Data)

RSS Syntax

The syntax rules of RSS 2.0 are very simple and very strict. The rules are very easy to learn, and very easy to use.

How RSS Works

RSS is used to share content between websites.

With RSS, you register your content with companies called aggregators.

So, to be a part of it: First, create an RSS document and save it with an .xml extension. Then, upload the file to your website. Next, register with an RSS aggregator. Each day the aggregator searches the registered websites for RSS documents, verifies the link, and displays information about the feed so clients can link to documents that interests them.

Tip: Read our RSS Publishing chapter to view free RSS aggregation services.

An Example RSS document

RSS documents use a self-describing and simple syntax.

Let's look at a simple RSS document:

<?xml version="1.0" encoding="ISO-8859-1" ?>
<rss version="2.0">

<channel>
  <title>W3Schools Home Page</title>
  <link>http://www.w3schools.com</link>
  <description>Free web building tutorials</description>
  <item>
    <title>RSS Tutorial</title>
    <link>http://www.w3schools.com/rss</link>
    <description>New RSS tutorial on W3Schools</description>
  </item>
  <item>
    <title>XML Tutorial</title>
    <link>http://www.w3schools.com/xml</link>
    <description>New XML tutorial on W3Schools</description>
  </item>
</channel>

</rss>

The first line in the document - the XML declaration - defines the XML version and the character encoding used in the document. In this case the document conforms to the 1.0 specification of XML and uses the ISO-8859-1 (Latin-1/West European) character set.

The next line is the RSS declaration which identifies that this is an RSS document (in this case, RSS version 2.0).

The next line contains the <channel> element. This element is used to describe the RSS feed.

The <channel> element has three required child elements:

<title> - Defines the title of the channel (e.g. W3Schools Home Page)
<link> - Defines the hyperlink to the channel (e.g. http://www.w3schools.com)
<description> - Describes the channel (e.g. Free web building tutorials)

Each <channel> element can have one or more <item> elements.

Each <item> element defines an article or "story" in the RSS feed.

The <item> element has three required child elements:

<title> - Defines the title of the item (e.g. RSS Tutorial)
<link> - Defines the hyperlink to the item (e.g. http://www.w3schools.com/rss)
<description> - Describes the item (e.g. New RSS tutorial on W3Schools)

Finally, the two last lines close the <channel> and <rss> elements.

Comments in RSS

The syntax for writing comments in RSS is similar to that of HTML:

<!-- This is an RSS comment -->

RSS is Written in XML

Because RSS is XML, keep in mind that:

All elements must have a closing tag
Elements are case sensitive
Elements must be properly nested
Attribute values must always be quoted