RFC 4287: The Atom Syndication Format
- Official specification for the XML-based document format that describes lists of related information known as "feeds".
- http://tools.ietf.org/html/rfc4287

How to Make a Good ID in Atom
- Advice on constructing ID values from Mark Pilgrim.
- http://diveintomark.org/archives/2004/05/28/howto-atom-id

Blogger Help : What is Atom?
- Blogger uses Atom for its syndication feed format. This page gives details for the nontechnically-minded blogger.
- http://help.blogger.com/bin/answer.py?answer=42014

Atom Enabled
- News and announcements relating to the Atom syndication format.
- http://www.atomenabled.org/atom.xml

Atom Wiki
- Work area for writing specifications for syndicating, archiving and editing episodic web sites.
- http://www.intertwingly.net/wiki/pie/

IETF Atom Publishing Format and Protocol Working Group
- Description, members and goals.
- http://www.ietf.org/html.charters/atompub-charter.html

Wikipedia: Atom (standard)
- Encyclopedia article about the atom standards, including history, motivation, and a comparison with RSS.
- http://en.wikipedia.org/wiki/Atom_(standard)

AtomEnabled.org
- Atom is a way to read and write information on the web, and is considered a competitor/alternate format to RSs. Basic information about the format as well as on software and services which use or can read Atom data.
- http://www.atomenabled.org/