GNOME and KDE.
Some of the Linux desktop environments that are available are: Unity, Cinnamon, Gnome, Sugar, Enlightenment, Mezzo, Xfce, Xmonad, KDE, MATE, LXDE, and ROX.
There are several desktop environments for Linux currently in use. The most popular are GNOME and KDE.
It's a command to start the X server for running Linux in graphical mode, if you have any of the desktop environments and/or window managers installed.
No. There is no single user interface for Linux. GNOME. KDE, Xfce, Fluxbox, and CDE are all examples of user interfaces / desktop environments for Linux.
Red Hat Linux was discontinued in 2004 in favour of Red Hat Enterprise Linux for enterprise environments. However, Red Hat Linux still exists as "Fedora", free for home use, developed by "Fedora Projects", though the entire line is no longer commercial and only supported by the Linux community.
The most often used X Window (graphical) desktop environments are KDE and GNOME. There are many others.
No! In addition to Mac OS X, there are several Linux distributions with a wide selection of desktop environments. Although it's seen better days, AmigaOS is also a desktop operating system.
gnome and kde
Red Hat Enterprise Linux - produced by Red Hat SUSE Linux Enterprise Server - produced by Novell Ubuntu (available free of charge, but has paid support available) - produced by Canonical.
Microsoft should and does consider Linux a threat in the enterprise desktop and server market. They are also in danger of losing market share in netbooks and ultralight laptops.
Yes it is possible to do so. Once you have them, at the login screen you should find an option that allows you to choose which desktop environment you want to use.
SUSE Linux Enterprise Server was created in 1994.