1 Linux Mint - Cinnamon, Mate - everybody's favorite for a reason. Good for beginners.

2 Ubuntu - Unity - Good for beginners - base distribution for many other distributions

Note: The Unity user interface, like the Windows 8 user interface, is being optimized for cell phones and tablets. The desktop is being deprecated. If you are an XP user considering Linux to get away from Windows 8, Unity may not be a good choice.

3 Debian - GNOME, KDE - not for beginners.

Note: Base distribution of base distributions, especially Ubuntu

4 openSUSE - Blackbox Desktop - sponsored by Novell - goals: easiest to obtain, most usable.

5 Fedora - Awesome - Red Hat base distribution.

Note: "Awesome" is the name of the desktop, it is not my opinion of the desktop.

6 Arch - Cinnamon - targeted at competent Linux users. If you can use Arch, you are an experienced Linux user.

7 Mageia - KDE - a fork of Mandriva Linux. Nice distribution

Note: the KDE distribution is better than the GNOME distribution for Mageia.

8 elementary - Pantheon (Gnome) -

Note: I have looked at elementary a couple of times. I could never get excited, or interested, or remember exactly what it is like.

9 Zorin - GNOME, LXDE - designed especially for newcomers to Linux. It has a Windows-like graphical user interface.

Note: If you are a Windows XP user who is considering Linux, look at Linux Mint Cinnamon, and Zorin. I would pick Linux Mint, but a lot of XP users after considering both, pick Zorin.

10 Bodhi - Enlightenment window manager

11 Lubuntu - LXDE

12 Pinguy - Gnome - targeted at beginning Linux users

13 Puppy - boots into a ramdisk and loads into RAM

14 Tails - GNOME - Live CD providing complete Internet anonymity for the user

15 SteamOS - GNOME - designed to run Valve's Steam and Steam games

16 CentOS - Red Hat Enterprise Linux clone -

17 Voyager - Xfce -

18 Xubuntu - Xfce

19 LXLE - LXDE

20 wattOS - LXDE, Mate, Openbox - strives to be as energy-efficient as possible for low-spec and recycled computers