Intro
What is Mozilla?
Mozilla, in the most concise form, is a web application. To be more precise, it is a suite of applications containing a browser, a mail client, and more. If you are referring to Mozilla as a organization, which is also true, it is an organization that creates the web suite, sub-projects involved with the web suite, a series of products that have spinned off that were created to aid the development of the web suite, spinoffs of the web suite itself, and more.
Mozilla and Netscape
Mozilla and Netscape have had an interesting relationship. Netscape was the company that created the open-source Mozilla project by contributing pre-5.0 Netscape beta code. This code was eventually abandoned in favor of a ground-up rewrite of the browser, from which future Netscape releases were made. Although it came too late to help Netscape in the Browser Wars, beta versions of the Mozilla Suite formed the basis for Netscape 6.x versions, and the version 1.0 release of Mozilla was combined with proprietary components such as AIM and Netscape Radio to create Netscape 7.
The Gecko Rendering Engine
The Gecko rendering engine is the code that decides how all that (X)HTML, CSS, Javascript, etc. should be displayed. Its reputation, which is well deserved, is to be a very modern, standards-support engine, at the loss of support for sites that have long been not well-coded or something along those lines simply because Internet Explorer displays it without a hitch. However, those errors are far and few between and the Gecko rendering engine is usually a blessing for web developers who want to dabble in the latest and the newest in web technologies such as: SVG, XML, XSL, CSS, XHTML, DOM, and others. Beyond that, it works silently in the background to translate code into web pages.
