Gecko is the name of the layout engine developed by the Mozilla Project. It was originally named NGLayout. Gecko's function is to render web content, such as HTML, CSS, XUL, JavaScript, and render it on the user's screen or print it. In XUL-based applications Gecko also renders the application's user interface.

Gecko is used in many applications, including a few browsers such as Firefox and SeaMonkey (for a complete list, please refer to Wikipedia's article on Gecko). Products using the same version of Gecko have identical support for Web standards.



This page contains information specific to browser chrome (not Google Chrome) code running in Gecko.

Gecko FAQ
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.
Embedding Mozilla
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.

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