Forum Moderators: open
title: The title of the item.
link: The URL of the item.
description: The item synopsis.
author: Email address of the author of the item.
category: Includes the item in one or more categories.
comments: URL of a page for comments relating to the item.
enclosure: Describes a media object that is attached to the item.
guid: A string that uniquely identifies the item.
pubDate: Indicates when the item was published.
source: The RSS channel that the item came from.
The idea of the RSS feed is to show a description and then take the user to the content. I am not sure exactly how two descriptions would be useful but that doesn't mean that I know everything.
<rss version="2.0" xmlns:ExtraField="http://www.mydomain.com/ExtraField#">
...
<item>
<title>..</title>
<pubDate>..</pubDate>
<description>..</description>
<ExtraField:LongDesc>....</ExtraField:LongDesc>
..
</item>
credit to Extending RSS 2.0 With Namespaces [disobey.com]