Centos 7 disable desktop environment

Centos has changed a lot by the newcoming member 7 of it. It is ideal to use for server environments. When installed by live cd, graphical desktop environment is installed and loaded default when booting.
Because the system is changed a lot tutorials found on internet for Centos 5 or 6 are not valid for this new edition. Instead a very simple way is documented on official documentation.
By the following command you find default target which is presumably graphical.target after installation  

$ systemctl get-default

 
And then it is easily changed to console login by

$ systemctl set-default multi-user.target