Gecko is used in many applications, including a few browsers, such as Firefox, SeaMonkey, etc. (for a complete list, please refer to Wikipedia's article on Gecko.) Products using the same version of Gecko have identical support for standards.
Frequently asked questions about Gecko.
Gecko DOM reference
Reference to the DOM.
Gecko event reference
Reference to events used within Gecko and Mozilla applications; for web-standard DOM events, see the DOM event reference.
Gecko versions and application versions
Versions of Gecko and the applications they're used in.
Introduction to Layout in Mozilla
Tech Talk on layout.
Using Gecko in your own application.
Character sets supported by Gecko
A list of the character sets supported by Gecko.
HTML parser threading
Description of multithreading in the HTML parser.
Gecko Home Page on MozillaWiki
Home for the active developers. Roadmaps and more up-to-date resources.
Web Standards, XUL, Embedding Mozilla, Developing Mozilla
Document Tags and Contributors
Contributors to this page: Bielawski
, Jürgen Jeka
, Mathieu Deaudelin
, Pleasant Cry
, juergen jeka