Atom is the name of an XML-based Web content and metadata syndication format, and an application-level protocol for publishing and editing Web resources belonging to periodically updated websites.
Atom is a relatively recent spec and is much more robust and feature-rich than RSS. For instance, where RSS requires descriptive fields such as title and link only in item breakdowns, Atom requires these things for both items and the full Feed.
All Atom Feeds must be well-formed XML documents, and are identified with the application/atom+xml media type.
A Feed consists of some metadata, followed by any number of entries. Here is a basic structure of an Atom 1.0 Feed.
<?xml version="1.0"?> <feed xmlns="http://www.w3.org/2005/Atom"> <title>...</title> <link>...</link> <updated>...</updated> <author> <name>...</name> </author> <id>...</id> <entry> <title>...</title> <link>...</link> <id>...</id> <updated>...</updated> <summary>...</summary> </entry> </feed>
An Atom 1.0 Feed Document will be constructed of the following two elements:
There are some common construct, which are required for the above two elements and they are explained in: Common Construct.