MDN / Gecko
MDN / Gecko
Gecko is the layout engine developed by the Mozilla Project and used in many apps/devices, including and .
Web need software called a layout engine to interpret , , , and embedded content (like images) and draw everything to your screen. Besides this, Gecko makes sure associated work well on every operating system Gecko supports, and that appropriate APIs are exposed only to relevant support targets. This means that Gecko includes, among other things, a networking stack, graphics stack, layout engine, a JavaScript virtual machine, and porting layers.
Since all Firefox OS apps are Web apps, Firefox OS uses Gecko as its app runtime as well.
See also
Gecko on Wikipedia