This is a good little intro to the world of Linux. It contains some interesting facts that some people might not know, such as:

• Linux powers 446 of the world's top 500 supercomputers.
• Director James Cameron again chose Linux servers for box-office smash Avatar.
• Google runs its web servers on Linux.
• In 2009, Linux had 33.8% revenue marketshare of servers, compared to Microsoft's 7.3%

http://www.baselinemag.com/c/a/Intelligence/40-Fast-Facts-on-Linux-727574/