Desktop environment

What is a desktop environment? Simply put a desktop environment is a collection of programs running on top of an OS (operating system) that makes up the desktop Graphical User Interface. In the case of Windows and OS X, there is just the one desktop environment. Gnu+Linux does not have this limitation, though. In the world of Gnu+Linux there are many desktop environments to choose from GNOME, KDE, and Xfce are three of the most popular desktop environments. However there are many more to choose from like 

Enlightenment, Cinnamon, and Mate to name a few. Each desktop environment includes built-in applications like web browsers and file managers. Those interfaces tend to be more customizable plus all Gnu programs are run with all gnu desktops, so you never have to worry about a program not working with a certain desktop environment.