How to repair your xserver

If you were playing with your video-drivers and suddenly found that your GUI for the desktop is gone,then what will you do?
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This may happen very often (especially if you are a beginner and reading various blogs about linux and trying different stuffs) so just after setting your machine do this:

cd /etc/X11 #check that 'X' is in caps
sudo cp xorg.conf xorg.conf.backup #this will copy the configuration file of your xserver the name xorg.conf.backup

Now if your GUI is gone then enter the safe mode by pressing ESC at grub menu , login as a root
do
cd /etc/X11
cp xorg.conf.backup xorg.conf

and then reboot using
shutdown -r now

You will get your desktop back.