[The_Victor]

I may need to correct myself. My first search didn't turn up any links, but this pretty much indicates that Gecko is based on Mozilla.

An Innovative Technology for Internet Client Products
Gecko, formerly code-named NGT, is Netscape's next-generation browsing engine. Gecko, an innovative technology for Internet client products, includes a high-performance browser engine and enables a graphical user interface based on open Internet standards. Gecko forms the foundation for faster, smaller, standards-based client software and has been developed through the open source model of mozilla.org.The modular design of Gecko enables the development of applications for a wide array of computing platforms, devices, and information appliances. All major future client products from Netscape will include Gecko.

Write Once, Browse Anywhere
Gecko's modular design enables Internet browsing anywhere and extends the power of the Internet to virtually any application, operating system, or device.

• Any Application. The modular nature of the Gecko engine makes browsing possible through easy integration in a wide variety of applications. Through Gecko, Internet browsing can immediately be integrated right in favorite applications, such as instant messaging and chat, email, finance, and gaming software.
• Any Operating System. The Gecko browsing engine is available for multiple platforms such as Windows, Mac OS, and Linux and can easily be ported to many additional operating systems.
• Any Device. Gecko is designed to power numerous consumer devices, including handheld phones, PDAs, fax machines, and TV set-top boxes. Through Gecko, access to the web can become even more pervasive. Gecko can allow consumers to use their favorite devices to access stock quotes and make trades while on the go or to order take-out food and shop for the holidays from the comfort of their living rooms.
• Any Developer. Software developers have free access to Gecko's source code, enabling them to customize Gecko and giving them maximum flexibility. The code is available for download from mozilla.org.

Key Benefits

• Small and Modular. Gecko is very small and modular yet delivers rich functionality. In fact, the first developer preview distributed in December 1998 fit on a floppy disk! This enables the creation of Internet client products that can potentially be used on a wide array of computing platforms, devices, and appliances.
• Support for Leading Internet Standards. Gecko features industry-leading Internet standards support. This includes full support for the W3C specifications for HTML 4.0, Cascading Style Sheets, level 1 (CSS-1), the W3C Document Object Model, level 1 (DOM1), Resource Description Framework (RDF), and XML. In addition, full support for these Internet standards enables their use for building user interfaces - for example, the browser's toolbars. This innovative use of standards means that content, web applications, and the user interface of applications such as the browser can be built once to run on multiple computing platforms.
• Speed. Gecko is very high performance, which enables the creation of extremely fast Internet clients.
• Open Source Development. These technologies have been developed in conjunction with mozilla.org. Open Source helps ensure that the standards implementations are fully compliant with the W3C standards.