Gecko (layout engine)
Encyclopedia
Gecko is a free and open source layout engine
used in many applications developed by Mozilla Foundation
and the Mozilla Corporation
(notably the Firefox
web browser), as well as in many other open source software projects.
It is designed to support open
Internet standards
, and is used by different applications to display web page
s and, in some cases, an application's user interface
itself (by rendering XUL). Gecko offers a rich programming API
that makes it suitable for a wide variety of roles in Internet-enabled applications, such as web browsers, content presentation, and client/server.
Gecko is written in C++
and is cross-platform
, and runs on various operating system
s including BSD
s, Linux
, Mac OS X
, Solaris, OS/2
, AIX, OpenVMS
, and Microsoft Windows
. Its development is now overseen by the Mozilla Foundation and is licensed by a tri-license of the Mozilla Public License
(MPL), GNU General Public License
(GPL) and GNU Lesser General Public License
(LGPL).
Gecko is the third most-common layout engine on the World Wide Web
, after Trident
(used by Internet Explorer
for Windows since version 4
) and WebKit
(used by Safari
and Google Chrome
), and followed by Presto
(used by Opera
).
. The existing Netscape rendering engine, originally written for Netscape Navigator
1.0 and upgraded through the years, was widely considered to be inferior to the one used in Microsoft Internet Explorer. It was slow, did not comply well with W3C standards, had limited support for dynamic HTML
and lacked features such as incremental reflow (when the layout engine rearranges elements on the screen as new data is downloaded and added to the page). The new layout engine was developed in parallel with the old, with the intention being to integrate it into Netscape Communicator when it was mature and stable. At least one more major revision of Netscape was expected to be released with the old layout engine before the switch.
After the launch of the Mozilla project in early 1998, the new layout engine code was released under an open-source license. Originally unveiled as Raptor, the name had to be changed to NGLayout (next generation layout) due to trademark
problems. Netscape later rebranded NGLayout as Gecko. While Mozilla Organization (the forerunner of the Mozilla Foundation
) initially continued to use the NGLayout name (Gecko was a Netscape trademark), eventually the Gecko branding won out.
In October 1998, Netscape announced that its next browser would use Gecko (which was still called NGLayout at the time) rather than the old layout engine, requiring large parts of the application to be rewritten. While this decision was popular with web standards advocates, it was largely unpopular with Netscape developers, who were unhappy with the six months given for the rewrite. It also meant that most of the work done for Netscape Communicator 5.0 (including development on the Mariner
improvements to the old layout engine) had to be abandoned. Netscape 6, the first Netscape release to incorporate Gecko, was released in November 2000 (the name Netscape 5 was never used).
As Gecko development continued, other applications and embedders began to make use of it. America Online, by this time Netscape's parent company, eventually adopted it for use in CompuServe
7.0 and AOL for Mac OS X (these products had previously embedded Internet Explorer). However, with the exception of a few betas
, Gecko was never used in the main Microsoft Windows
AOL client.
On July 15, 2003, AOL laid off the remaining Gecko developers and the Mozilla Foundation (formed on the same day) became the main steward of Gecko development. Today, Gecko is developed by employees of the Mozilla Corporation
, employees of companies that contribute to the Mozilla project, and volunteers.
Gecko also partially supports SVG
1.1.
In order to support web page
s designed for legacy versions of Netscape and Internet Explorer, Gecko supports DOCTYPE
switching. Documents with a modern DOCTYPE are rendered in standards compliance mode, which follows the W3C standards strictly. Documents that have no DOCTYPE or an older DOCTYPE are rendered in quirks mode
, which emulates some of the non-standard oddities of Netscape Communicator
4.x; however, some of the 4.x features (such as layers
) are not supported.
Gecko also has limited support for some non-standard Internet Explorer features, such as the marquee element and the
.
s, the earliest being Netscape 6
and Mozilla Application Suite
(later renamed SeaMonkey
). It is also used in other Mozilla web browser derivatives such as Firefox
, Camino
, Flock
, K-Meleon
and the implementation of Internet Explorer
that is part of Wine
.
Google's picture-organization software Picasa
(for Linux) is based on Gecko.
DevHelp
, a GTK+/GNOME browser for API documentation, uses Gecko for rendering docs.
Other products not included in the table include Swiftfox
, Portable Firefox, Fennec, Conkeror
, Classilla
, TenFourFox
, HP
Secure Web Browser, Oxygen, Minimo
, My Internet Browser, Sylera (for mobile), Thunderbird (email)
, Sunbird (calendar)
and Instantbird.
Gecko is also used by Sugar
for the OLPC XO-1
computer. Gecko is used as a complete implementation of the XUL
(XML
User Interface Language). Gecko currently defines the XUL specification.
The following table compares the different versions of Gecko:
. The Gecko engine also provides a versatile XML-based user interface rendering framework called XUL
that was used extensively in mail, newsgroup, and other programs. Another reason for much of the complexity in Gecko is the use of XPCOM
, a cross-platform
component model.
Layout engine
A web browser engine, , is a software component that takes marked up content and formatting information and displays the formatted content on the screen. It "paints" on the content area of a window, which is displayed on a monitor or a printer...
used in many applications developed by Mozilla Foundation
Mozilla Foundation
The Mozilla Foundation is a non-profit organization that exists to support and provide leadership for the open source Mozilla project. The organization sets the policies that govern development, operates key infrastructure and controls trademarks and other intellectual property...
and the Mozilla Corporation
Mozilla Corporation
The Mozilla Corporation is a wholly owned subsidiary of the Mozilla Foundation that coordinates and integrates the development of Internet-related applications such as the Mozilla Firefox and SeaMonkey Navigator web browsers and the Mozilla Thunderbird email client by a growing global community of...
(notably the Firefox
Mozilla Firefox
Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers...
web browser), as well as in many other open source software projects.
It is designed to support open
Open standard
An open standard is a standard that is publicly available and has various rights to use associated with it, and may also have various properties of how it was designed . There is no single definition and interpretations vary with usage....
Internet standards
Web standards
Web standards is a general term for the formal standards and other technical specifications that define and describe aspects of the World Wide Web. In recent years, the term has been more frequently associated with the trend of endorsing a set of standardized best practices for building web sites,...
, and is used by different applications to display web page
Web page
A web page or webpage is a document or information resource that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a monitor or mobile device. This information is usually in HTML or XHTML format, and may provide navigation to other web pages via hypertext...
s and, in some cases, an application's user interface
User interface
The user interface, in the industrial design field of human–machine interaction, is the space where interaction between humans and machines occurs. The goal of interaction between a human and a machine at the user interface is effective operation and control of the machine, and feedback from the...
itself (by rendering XUL). Gecko offers a rich programming API
Application programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
that makes it suitable for a wide variety of roles in Internet-enabled applications, such as web browsers, content presentation, and client/server.
Gecko is written in C++
C++
C++ is a statically typed, free-form, multi-paradigm, compiled, general-purpose programming language. It is regarded as an intermediate-level language, as it comprises a combination of both high-level and low-level language features. It was developed by Bjarne Stroustrup starting in 1979 at Bell...
and is cross-platform
Cross-platform
In computing, cross-platform, or multi-platform, is an attribute conferred to computer software or computing methods and concepts that are implemented and inter-operate on multiple computer platforms...
, and runs on various operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
s including BSD
Berkeley Software Distribution
Berkeley Software Distribution is a Unix operating system derivative developed and distributed by the Computer Systems Research Group of the University of California, Berkeley, from 1977 to 1995...
s, Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
, Mac OS X
Mac OS X
Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...
, Solaris, OS/2
OS/2
OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
, AIX, OpenVMS
OpenVMS
OpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is a computer server operating system that runs on VAX, Alpha and Itanium-based families of computers. Contrary to what its name suggests, OpenVMS is not open source software; however, the source listings are available for purchase...
, and Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
. Its development is now overseen by the Mozilla Foundation and is licensed by a tri-license of the Mozilla Public License
Mozilla Public License
The Mozilla Public License is a free and open source software license. Version 1.0 was developed by Mitchell Baker when she worked as a lawyer at Netscape Communications Corporation and version 1.1 at the Mozilla Foundation...
(MPL), GNU General Public License
GNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
(GPL) and GNU Lesser General Public License
GNU Lesser General Public License
The GNU Lesser General Public License or LGPL is a free software license published by the Free Software Foundation . It was designed as a compromise between the strong-copyleft GNU General Public License or GPL and permissive licenses such as the BSD licenses and the MIT License...
(LGPL).
Gecko is the third most-common layout engine on the World Wide Web
World Wide Web
The World Wide Web is a system of interlinked hypertext documents accessed via the Internet...
, after Trident
Trident (layout engine)
Trident is the name of the layout engine for the Microsoft Windows version of Internet Explorer.It was first introduced with the release of Internet Explorer version 4.0 in October 1997; it has been steadily upgraded and remains in use today...
(used by Internet Explorer
Internet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
for Windows since version 4
Internet Explorer 4
Microsoft Internet Explorer 4 is a graphical web browser released in September 1997 by Microsoft, primarily for Microsoft Windows, but also with versions available for Apple Mac OS, Solaris, and HP-UX and marketed as "The Web the Way You Want It".It was one of the main participants of the first...
) and WebKit
WebKit
WebKit is a layout engine designed to allow web browsers to render web pages. WebKit powers Google Chrome and Apple Safari and by October 2011 held over 33% of the browser market share between them. It is also used as the basis for the experimental browser included with the Amazon Kindle ebook...
(used by Safari
Safari (web browser)
Safari is a web browser developed by Apple Inc. and included with the Mac OS X and iOS operating systems. First released as a public beta on January 7, 2003 on the company's Mac OS X operating system, it became Apple's default browser beginning with Mac OS X v10.3 "Panther". Safari is also the...
and Google Chrome
Google Chrome
Google Chrome is a web browser developed by Google that uses the WebKit layout engine. It was first released as a beta version for Microsoft Windows on September 2, 2008, and the public stable release was on December 11, 2008. The name is derived from the graphical user interface frame, or...
), and followed by Presto
Presto (layout engine)
Presto is the layout engine for later versions of the Opera web browser . After several public betas and technical previews, it was released on January 28, 2003 in Opera 7 for Windows, and as of Opera 11 it is still in use. Presto is dynamic: the page or parts of it can be re-rendered in response...
(used by Opera
Opera (web browser)
Opera is a web browser and Internet suite developed by Opera Software with over 200 million users worldwide. The browser handles common Internet-related tasks such as displaying web sites, sending and receiving e-mail messages, managing contacts, chatting on IRC, downloading files via BitTorrent,...
).
History
Development of the layout engine now known as Gecko began at Netscape in 1997, following the company's purchase of DigitalStyleDigitalStyle
DigitalStyle was a small privately-held software company in Rancho Bernardo, San Diego, California. It was founded in 1995 by refugees from the failed software company Pages including Rick Gessner, Peter Linss, Greg Kostello, and James Hamerly...
. The existing Netscape rendering engine, originally written for Netscape Navigator
Netscape Navigator
Netscape Navigator was a proprietary web browser that was popular in the 1990s. It was the flagship product of the Netscape Communications Corporation and the dominant web browser in terms of usage share, although by 2002 its usage had almost disappeared...
1.0 and upgraded through the years, was widely considered to be inferior to the one used in Microsoft Internet Explorer. It was slow, did not comply well with W3C standards, had limited support for dynamic HTML
Dynamic HTML
Dynamic HTML, or DHTML, is an umbrella term for a collection of technologies used together to create interactive and animated web sites by using a combination of a static markup language , a client-side scripting language , a presentation definition language , and the Document Object Model.DHTML...
and lacked features such as incremental reflow (when the layout engine rearranges elements on the screen as new data is downloaded and added to the page). The new layout engine was developed in parallel with the old, with the intention being to integrate it into Netscape Communicator when it was mature and stable. At least one more major revision of Netscape was expected to be released with the old layout engine before the switch.
After the launch of the Mozilla project in early 1998, the new layout engine code was released under an open-source license. Originally unveiled as Raptor, the name had to be changed to NGLayout (next generation layout) due to trademark
Trademark
A trademark, trade mark, or trade-mark is a distinctive sign or indicator used by an individual, business organization, or other legal entity to identify that the products or services to consumers with which the trademark appears originate from a unique source, and to distinguish its products or...
problems. Netscape later rebranded NGLayout as Gecko. While Mozilla Organization (the forerunner of the Mozilla Foundation
Mozilla Foundation
The Mozilla Foundation is a non-profit organization that exists to support and provide leadership for the open source Mozilla project. The organization sets the policies that govern development, operates key infrastructure and controls trademarks and other intellectual property...
) initially continued to use the NGLayout name (Gecko was a Netscape trademark), eventually the Gecko branding won out.
In October 1998, Netscape announced that its next browser would use Gecko (which was still called NGLayout at the time) rather than the old layout engine, requiring large parts of the application to be rewritten. While this decision was popular with web standards advocates, it was largely unpopular with Netscape developers, who were unhappy with the six months given for the rewrite. It also meant that most of the work done for Netscape Communicator 5.0 (including development on the Mariner
Mariner (layout engine)
Mariner was a canceled project to add performance and stability enhancements to the layout engine used in the Netscape Communicator web browser...
improvements to the old layout engine) had to be abandoned. Netscape 6, the first Netscape release to incorporate Gecko, was released in November 2000 (the name Netscape 5 was never used).
As Gecko development continued, other applications and embedders began to make use of it. America Online, by this time Netscape's parent company, eventually adopted it for use in CompuServe
CompuServe
CompuServe was the first major commercial online service in the United States. It dominated the field during the 1980s and remained a major player through the mid-1990s, when it was sidelined by the rise of services such as AOL with monthly subscriptions rather than hourly rates...
7.0 and AOL for Mac OS X (these products had previously embedded Internet Explorer). However, with the exception of a few betas
Development stage
A software release life cycle refers to the phases of development and maturity for a piece of computer software—ranging from its initial development, to its eventual release, and updated versions of the released version to help improve software or fix bugs still present in the software.- Pre-alpha...
, Gecko was never used in the main Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
AOL client.
On July 15, 2003, AOL laid off the remaining Gecko developers and the Mozilla Foundation (formed on the same day) became the main steward of Gecko development. Today, Gecko is developed by employees of the Mozilla Corporation
Mozilla Corporation
The Mozilla Corporation is a wholly owned subsidiary of the Mozilla Foundation that coordinates and integrates the development of Internet-related applications such as the Mozilla Firefox and SeaMonkey Navigator web browsers and the Mozilla Thunderbird email client by a growing global community of...
, employees of companies that contribute to the Mozilla project, and volunteers.
Standards support
From the outset, Gecko was designed to support open Internet standards. Some of the standards Gecko supports include:- HTMLHTMLHyperText Markup Language is the predominant markup language for web pages. HTML elements are the basic building-blocks of webpages....
4 (partial support for HTML5) - CSSCascading Style SheetsCascading Style Sheets is a style sheet language used to describe the presentation semantics of a document written in a markup language...
Level 2.1 (partial support for CSS 3) - JavaScriptJavaScriptJavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles....
1.8 (ECMAScriptECMAScriptECMAScript is the scripting language standardized by Ecma International in the ECMA-262 specification and ISO/IEC 16262. The language is widely used for client-side scripting on the web, in the form of several well-known dialects such as JavaScript, JScript, and ActionScript.- History :JavaScript...
3, and partial support for ECMAScript 5), implemented in SpiderMonkeySpiderMonkeySpiderMonkey is the code name for the first-ever JavaScript engine, written by Brendan Eich at Netscape Communications, later released as open source and now maintained by the Mozilla Foundation.-History:Eich "wrote JavaScript in ten days" in 1995,... - DOMDocument Object ModelThe Document Object Model is a cross-platform and language-independent convention for representing and interacting with objects in HTML, XHTML and XML documents. Aspects of the DOM may be addressed and manipulated within the syntax of the programming language in use...
Level 1 and 2 (partial support for DOM 3) - XMLXMLExtensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....
1.0 - XHTMLXHTMLXHTML is a family of XML markup languages that mirror or extend versions of the widely-used Hypertext Markup Language , the language in which web pages are written....
1.0 - XSLTXSLTXSLT is a declarative, XML-based language used for the transformation of XML documents. The original document is not changed; rather, a new document is created based on the content of an existing one. The new document may be serialized by the processor in standard XML syntax or in another format,...
and XPathXPathXPath is a language for selecting nodes from an XML document. In addition, XPath may be used to compute values from the content of an XML document...
, implemented in TransforMiiXTransforMiiXTransforMiiX is an XSLT processor used in Gecko browsers, such as Firefox, to transform XML into HTML.TransforMiiX identifies itself by setting the system property xsl:vendor as Transformiix.-External links:*... - MathMLMathMLMathematical Markup Language is an application of XML for describing mathematical notations and capturing both its structure and content. It aims at integrating mathematical formulae into World Wide Web pages and other documents...
- XFormsXFormsXForms is an XML format for the specification of a data processing model for XML data and user interface for the XML data, such as web forms...
(via an official extension) - RDFResource Description FrameworkThe Resource Description Framework is a family of World Wide Web Consortium specifications originally designed as a metadata data model...
Gecko also partially supports SVG
Scalable Vector Graphics
Scalable Vector Graphics is a family of specifications of an XML-based file format for describing two-dimensional vector graphics, both static and dynamic . The SVG specification is an open standard that has been under development by the World Wide Web Consortium since 1999.SVG images and their...
1.1.
In order to support web page
Web page
A web page or webpage is a document or information resource that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a monitor or mobile device. This information is usually in HTML or XHTML format, and may provide navigation to other web pages via hypertext...
s designed for legacy versions of Netscape and Internet Explorer, Gecko supports DOCTYPE
Document Type Declaration
A Document Type Declaration, or DOCTYPE, is an instruction that associates a particular SGML or XML document with a Document Type Definition...
switching. Documents with a modern DOCTYPE are rendered in standards compliance mode, which follows the W3C standards strictly. Documents that have no DOCTYPE or an older DOCTYPE are rendered in quirks mode
Quirks mode
In computing, quirks mode refers to a technique used by some web browsers for the sake of maintaining backward compatibility with web pages designed for older browsers, instead of strictly complying with W3C and IETF standards in standards mode....
, which emulates some of the non-standard oddities of Netscape Communicator
Netscape Communicator
Netscape Communicator was an Internet suite produced by Netscape Communications Corporation. Initially released in June 1997, Netscape Communicator 4.0 was the successor to Netscape Navigator 3.x and included more groupware features intended to appeal to enterprises.- Editions :Netscape...
4.x; however, some of the 4.x features (such as layers
Layer (HTML tag)
Layers were the core of a method of dynamic HTML programming specific to Netscape 4. Each layer was treated as a separate document object in JavaScript...
) are not supported.
Gecko also has limited support for some non-standard Internet Explorer features, such as the marquee element and the
document.all property (though pages explicitly testing for document.all will be told it is not supported). While this increases compatibility with many documents designed only for Internet Explorer, some purists argue that it harms the cause of standards evangelismTechnology evangelist
A technical or technology evangelist is a person who attempts to build a critical mass of support for a given technology in order to establish it as a technical standard in a market that is subject to network effects...
.
Usage
Gecko is primarily used in web browserWeb browser
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content...
s, the earliest being Netscape 6
Netscape 6
Netscape 6 was the name of Netscape Communications Corporation's proprietary cross-platform internet suite from versions 6.0–6.2.3. It superseded Netscape Communicator 4.8 and was replaced by the simply-named Netscape...
and Mozilla Application Suite
Mozilla Application Suite
The Mozilla Application Suite is a cross-platform integrated Internet suite. Its development was initiated by Netscape Communications Corporation, before their acquisition by AOL. It is based on the source code of Netscape Communicator...
(later renamed SeaMonkey
SeaMonkey
SeaMonkey is a free and open source cross-platform Internet suite. It is the continuation of the former Mozilla Application Suite, based on the same source code...
). It is also used in other Mozilla web browser derivatives such as Firefox
Mozilla Firefox
Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers...
, Camino
Camino
Camino is a free, open source, GUI-based Web browser based on Mozilla's Gecko layout engine and specifically designed for the Mac OS X operating system...
, Flock
Flock (web browser)
Flock was a web browser that specialized in providing social networking and Web 2.0 facilities built into its user interface.Earlier versions of Flock used the Gecko HTML rendering engine by Mozilla....
, K-Meleon
K-Meleon
K-Meleon is a web browser for the Microsoft Windows platform. Based on the same Gecko layout engine as Mozilla Firefox, K-Meleon uses native Windows application programming interface to create the user interface, instead of using Mozilla's cross-platform XML User Interface Language layer, and as...
and the implementation of Internet Explorer
Internet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
that is part of Wine
Wine (software)
Wine is a free software application that aims to allow computer programs written for Microsoft Windows to run on Unix-like operating systems. Wine also provides a software library, known as Winelib, against which developers can compile Windows applications to help port them to Unix-like...
.
Google's picture-organization software Picasa
Picasa
Picasa is an image organizer and image viewer for organizing and editing digital photos, plus an integrated photo-sharing website, originally created by Idealab in 2002 and owned by Google since 2004. "Picasa" is a blend of the name of Spanish painter Pablo Picasso, the phrase mi casa for "my...
(for Linux) is based on Gecko.
DevHelp
Devhelp
Devhelp is a GTK+/GNOME browser for API documentation; it works natively with gtk-doc ....
, a GTK+/GNOME browser for API documentation, uses Gecko for rendering docs.
Other products not included in the table include Swiftfox
Swiftfox
Swiftfox is a web browser based on Mozilla Firefox. It is available for GNU/Linux platforms and distributed by Jason Halme. Swiftfox is a set of builds of Firefox optimized for different Intel and AMD microprocessors. Swiftfox is freely downloadable with open source code and proprietary binaries....
, Portable Firefox, Fennec, Conkeror
Conkeror
Conkeror is a Mozilla-based web browser designed to be navigated primarily by a computer keyboard. Its design is mainly patterned after the text editor GNU Emacs, with some influence from other programs, including vi....
, Classilla
Classilla
Classilla is a Gecko-based web browser for PowerPC-based classic Macintosh systems, essentially an updated descendant of the now-defunct Mozilla Application Suite by way of the Mac OS port maintained in the now-aborted project...
, TenFourFox
TenFourFox
TenFourFox is a Mozilla-based browser closely related to Mozilla Firefox, written for PowerPC-based Macintosh computers running Mac OS X to retain compatibility with the older architecture and older versions of the operating system, and to add PowerPC-specific optimizations for improved performance...
, HP
Hewlett-Packard
Hewlett-Packard Company or HP is an American multinational information technology corporation headquartered in Palo Alto, California, USA that provides products, technologies, softwares, solutions and services to consumers, small- and medium-sized businesses and large enterprises, including...
Secure Web Browser, Oxygen, Minimo
Minimo
Minimo was a project to create a version of the Mozilla web browser for small devices like PDAs and mobile phones.The project aimed to make it easier for developers to embed parts of Mozilla into systems with limited system resources...
, My Internet Browser, Sylera (for mobile), Thunderbird (email)
Mozilla Thunderbird
Mozilla Thunderbird is a free, open source, cross-platform e-mail and news client developed by the Mozilla Foundation. The project strategy is modeled after Mozilla Firefox, a project aimed at creating a web browser...
, Sunbird (calendar)
Mozilla Sunbird
Mozilla Sunbird is a free and open source, cross-platform calendar application that was developed by the Mozilla Foundation, Sun Microsystems and many volunteers...
and Instantbird.
Gecko is also used by Sugar
Sugar (GUI)
Sugar is an open source desktop environment designed with the goal of being used by children for learning.Developed as part of the One Laptop per Child project, it is the default interface on OLPC XO-1 family of laptop computers....
for the OLPC XO-1
OLPC XO-1
The XO-1, previously known as the $100 Laptop, Children's Machine, and 2B1, is an inexpensive subnotebook computer intended to be distributed to children in developing countries around the world, to provide them with access to knowledge, and opportunities to "explore, experiment and express...
computer. Gecko is used as a complete implementation of the XUL
XUL
In computer programming, XUL , the XML User Interface Language, is an XML user interface markup language developed by the Mozilla project. XUL operates in Mozilla cross-platform applications such as Firefox...
(XML
XML
Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....
User Interface Language). Gecko currently defines the XUL specification.
The following table compares the different versions of Gecko:
| Gecko version | All platforms | Windows only | Mac only | *nix only | *nix mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Firefox Mozilla Firefox Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers... |
Netscape Netscape Netscape Communications is a US computer services company, best known for Netscape Navigator, its web browser. When it was an independent company, its headquarters were in Mountain View, California... |
Mozilla Mozilla Application Suite The Mozilla Application Suite is a cross-platform integrated Internet suite. Its development was initiated by Netscape Communications Corporation, before their acquisition by AOL. It is based on the source code of Netscape Communicator... |
SeaMonkey SeaMonkey SeaMonkey is a free and open source cross-platform Internet suite. It is the continuation of the former Mozilla Application Suite, based on the same source code... |
Flock Flock (web browser) Flock was a web browser that specialized in providing social networking and Web 2.0 facilities built into its user interface.Earlier versions of Flock used the Gecko HTML rendering engine by Mozilla.... |
Songbird Songbird (software) Songbird is a free and open source software audio player and web browser, with a stated mission "to incubate Songbird, the first Web player, to catalyze and champion a diverse, open Media Web."... |
Beonex Beonex Communicator Beonex Communicator was an open source internet suite based on the Mozilla Application Suite by Ben Bucksch, a German Mozilla developer, which have a higher security and privacy level than other commercial products.... |
Lunascape Lunascape (web browser) Lunascape is a web browser developed by Lunascape Corporation in Tokyo, Japan. It is unique in that it contains three rendering engines: Gecko , WebKit , and Trident... |
K-Meleon K-Meleon K-Meleon is a web browser for the Microsoft Windows platform. Based on the same Gecko layout engine as Mozilla Firefox, K-Meleon uses native Windows application programming interface to create the user interface, instead of using Mozilla's cross-platform XML User Interface Language layer, and as... |
My Internet Browser | Pale Moon Pale Moon (web browser) Pale Moon is a web browser based on Mozilla Firefox. It uses the Mozilla back-end . It is available for Windows platforms and distributed by Moonchild . Pale Moon builds on Firefox, optimizing for efficiency of code and aimed at current and modern microprocessors. Pale Moon is freely downloadable... |
Camino Camino Camino is a free, open source, GUI-based Web browser based on Mozilla's Gecko layout engine and specifically designed for the Mac OS X operating system... |
Galeon Galeon Galeon is a web browser for GNOME based on Mozilla’s Gecko layout engine. Galeon’s self-declared mission was to deliver the web and only the web. Galeon was discontinued in September 2008.... |
Epiphany | Kazehakase Kazehakase Kazehakase is a web browser for Unix-like operating systems that uses the GTK+ libraries. Kazehakase embeds the Gecko layout engine as well as GTK+ WebKit. However, the author also plans to add the ability to switch between additional different rendering engines... |
MicroB MicroB MicroB is a mobile web browser developed by Nokia for use in smartphones and mobile devices that run the Maemo operating system. The browser is Mozilla-based and uses the Gecko layout engine.... |
|
| 0.6 | 6.0 Netscape 6 Netscape 6 was the name of Netscape Communications Corporation's proprietary cross-platform internet suite from versions 6.0–6.2.3. It superseded Netscape Communicator 4.8 and was replaced by the simply-named Netscape... |
0.6 | 0.6 | |||||||||||||
| 0.8 | 0.8 | 0.3 | ||||||||||||||
| 0.9.2 | 6.1 | 0.9.2 | ||||||||||||||
| 0.9.4 | 6.2 | 0.9.4 | 0.5 | |||||||||||||
| 0.9.4.1 | 6.2.2 | 0.9.4.1 | 0.7 | |||||||||||||
| 0.9.5 | 0.9.5 | 0.6 | ||||||||||||||
| 0.9.7 | 0.9.7 | 1.0.2 | ||||||||||||||
| 1.0.1 | 7.0 | 1.0.1 | 0.8.1 | |||||||||||||
| 1.0.2 | 1.0.2 | 0.8.2 | ||||||||||||||
| 1.1 | 1.1 | 0.9pre | ||||||||||||||
| 1.2b | 0.1 | 1.2b | 0.7 | |||||||||||||
| 1.3a | 0.5 | 1.3a | ||||||||||||||
| 1.4 | 7.1 | 1.4 | ||||||||||||||
| 1.4.1 | 1.4.1 | 1.0.4 | ||||||||||||||
| 1.5 | 0.7 | 1.5 | 0.8 | |||||||||||||
| 1.7 | 1.0 | 1.7 | 2.0 | 0.2.8 | ||||||||||||
| 1.7.2 | 7.2 | 1.7.2 | ||||||||||||||
| 1.7.5 | 8.0.2 Netscape Browser Netscape Browser is the name of a proprietary Windows web browser published by AOL, but developed by Mercurial Communications. It is the eighth major release in name of the Netscape series of browsers, originally produced by the defunct Netscape Communications Corporation.While Netscape Browser's... |
1.7.5 | 0.9 | |||||||||||||
| 1.8.0 | 1.5 | 1.0 | 0.7 | 0.2 | 1.0 | 1.0 | 1.0 | |||||||||
| 1.8.1 | 2.0 Mozilla Firefox 2 Mozilla Firefox 2 was a version of Firefox, a web browser released on October 24, 2006 by the Mozilla Corporation.Firefox 2 uses version 1.8 of the Gecko layout engine for displaying web pages... |
9.0 | 1.1 | 1.0 | 4.8 | 1.1, 1.5 | 2.0 | 1.6.5 | 2.16 | |||||||
| 1.9.0 | 3.0 Mozilla Firefox 3 Mozilla Firefox 3.0 is a version of the Firefox web browser released on June 17, 2008 by the Mozilla Corporation.Firefox 3.0 uses version 1.9 of the Gecko layout engine for displaying web pages. This version fixes many bugs, improves standard compliance, and implements many new web APIs compared to... |
2.0 - 2.6 | 0.5 - 1.4 | 2.2 | 2.0 | 2.22 | ||||||||||
| 1.9.1 | 3.5 Mozilla Firefox 3.5 Mozilla Firefox 3.5 is a version of the Firefox web browser released in June 2009, adding a variety of new features to Firefox. Version 3.5 was touted as being twice as fast as 3.0... |
2.0 | 5.0 | 1.6 | 3.0 | 3.5 | ||||||||||
| 1.9.2 | 3.6 Mozilla Firefox 3.6 Mozilla Firefox 3.6 is a version of the Firefox web browser released in January 2010. The release's main improvement over Firefox 3.5 is improved performance . It uses the Gecko 1.9.2 engine , which improves compliance with web standards... |
1.9.3 | 6.3 | 1.7 | 4.0 | 3.6 | 2.1a1 | 1.7.4.8 | ||||||||
| 2.0 | 4.0 Mozilla Firefox 4 Mozilla Firefox 4 is a version of the Firefox web browser, released on 22 March 2011. The first beta was made available on 6 July 2010; Release Candidate 2 was released on 18 March 2011. It was codenamed Tumucumaque, and has been confirmed as Firefox's last large release cycle... |
2.1 | 4.0 | |||||||||||||
| 5.0 | 5.0 | 2.2 | 5.0 | |||||||||||||
| 6.0 | 6.0 | 2.3 | 6.0 | |||||||||||||
| 7.0 | 7.0 | 2.4 | 7.0 | |||||||||||||
| 8.0 | 8.0a2 | |||||||||||||||
| 9.0 | 9.0a1 | |||||||||||||||
| Gecko version | Firefox Mozilla Firefox Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers... |
Netscape Netscape Netscape Communications is a US computer services company, best known for Netscape Navigator, its web browser. When it was an independent company, its headquarters were in Mountain View, California... |
Mozilla Mozilla Application Suite The Mozilla Application Suite is a cross-platform integrated Internet suite. Its development was initiated by Netscape Communications Corporation, before their acquisition by AOL. It is based on the source code of Netscape Communicator... |
SeaMonkey SeaMonkey SeaMonkey is a free and open source cross-platform Internet suite. It is the continuation of the former Mozilla Application Suite, based on the same source code... |
Flock Flock (web browser) Flock was a web browser that specialized in providing social networking and Web 2.0 facilities built into its user interface.Earlier versions of Flock used the Gecko HTML rendering engine by Mozilla.... |
Songbird Songbird (software) Songbird is a free and open source software audio player and web browser, with a stated mission "to incubate Songbird, the first Web player, to catalyze and champion a diverse, open Media Web."... |
Beonex Beonex Communicator Beonex Communicator was an open source internet suite based on the Mozilla Application Suite by Ben Bucksch, a German Mozilla developer, which have a higher security and privacy level than other commercial products.... |
Lunascape Lunascape (web browser) Lunascape is a web browser developed by Lunascape Corporation in Tokyo, Japan. It is unique in that it contains three rendering engines: Gecko , WebKit , and Trident... |
K-Meleon K-Meleon K-Meleon is a web browser for the Microsoft Windows platform. Based on the same Gecko layout engine as Mozilla Firefox, K-Meleon uses native Windows application programming interface to create the user interface, instead of using Mozilla's cross-platform XML User Interface Language layer, and as... |
My Internet Browser | Pale Moon Pale Moon (web browser) Pale Moon is a web browser based on Mozilla Firefox. It uses the Mozilla back-end . It is available for Windows platforms and distributed by Moonchild . Pale Moon builds on Firefox, optimizing for efficiency of code and aimed at current and modern microprocessors. Pale Moon is freely downloadable... |
Camino Camino Camino is a free, open source, GUI-based Web browser based on Mozilla's Gecko layout engine and specifically designed for the Mac OS X operating system... |
Galeon Galeon Galeon is a web browser for GNOME based on Mozilla’s Gecko layout engine. Galeon’s self-declared mission was to deliver the web and only the web. Galeon was discontinued in September 2008.... |
Epiphany | Kazehakase Kazehakase Kazehakase is a web browser for Unix-like operating systems that uses the GTK+ libraries. Kazehakase embeds the Gecko layout engine as well as GTK+ WebKit. However, the author also plans to add the ability to switch between additional different rendering engines... |
MicroB MicroB MicroB is a mobile web browser developed by Nokia for use in smartphones and mobile devices that run the Maemo operating system. The browser is Mozilla-based and uses the Gecko layout engine.... |
| All platforms | Windows only | Mac only | *nix only | *nix mobile | ||||||||||||
Criticism
One of the primary reasons for slower market share adoption is the complexity of the Gecko code which aims to provide much more than just an HTML renderer for web browserWeb browser
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content...
. The Gecko engine also provides a versatile XML-based user interface rendering framework called XUL
XUL
In computer programming, XUL , the XML User Interface Language, is an XML user interface markup language developed by the Mozilla project. XUL operates in Mozilla cross-platform applications such as Firefox...
that was used extensively in mail, newsgroup, and other programs. Another reason for much of the complexity in Gecko is the use of XPCOM
XPCOM
XPCOM is a cross-platform component model from Mozilla. It is similar to Microsoft COM and CORBA. It has multiple language bindings and IDL descriptions so programmers can plug their custom functionality into the framework and connect it with other components.-The model:XPCOM is one of the main...
, a cross-platform
Cross-platform
In computing, cross-platform, or multi-platform, is an attribute conferred to computer software or computing methods and concepts that are implemented and inter-operate on multiple computer platforms...
component model.
External links
- Gecko - Mozilla Developer Center
- Gecko development wiki (wiki.mozilla.org)
- Gecko Layout Engine - Real-time Reflow Videos
- Mozilla Product Strategy Proposal (DRAFT)
- Web Browser Standards Support
- JRex (JavaJava (programming language)Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities...
API for Gecko)