On April 19 2011 I gave the laboratory lesson of the 7th edition of the GNU/Linux Course (spring 2011) organized by the student association NetStudent of the Polytechnic of Turin and freely accessible to anyone interested in discovering this fantastic operating system.
The internet as we know it today predominantly runs on Linux. There’s an extremely high probability that the internet connection you’re using right now is connected thru a Linux server – and routed thru many other Linux servers along the way.