Gecko also includes a set of complementary browser components that work alongside the layout engine to form the founding platform for the Mozilla browser and for products from commercial vendors such as Netscape 6, the AOL-Gateway browsing appliance, and others.
Gecko is continously under development at mozilla.org.
Formally, a layout engine defines the placement policy for a document and places content on a page. Gecko's core is a very fast layout engine. In other words, Gecko will not only be displaying the document's content, but it will also be painting the scroll bars, tool bars, and menus on the screen as well. Gecko provides the foundation needed to display content on the screen, including a layout engine and a complementary set of browser components. Other companies will release their own software and hardware products that embed Gecko.