Gnome and other desktop environments like it differ from "window managers" or windowing systems in that they provide a middle-ware capacity for the display layer in an operating system. A "desktop" environment defines all of the "widgets" that programs can use to display their user interfaces, from textboxes to buttons to scrollbars.

It is a GNU project, and as such its goal is to develop a high-quality desktop for UNIX-like operating systems, such as Linux, as free software. A massive amount of progress has been made, of course, as Gnome is now light-years ahead of where it started.

Gnome was actually originally developed as a free alternative to the KDE Desktop environment over their use of a commercially licensed (and copyrighted) toolkit for displaying user interface widgets. KDE and Gnome have both developed in parallel and are both excellent systems, especially considering their cost. Gnome is available on most complete Linux distributions.