There are several fully functional and stable Open Source operating systems including Linux, FreeBSD, OpenSolaris, NetBSD, OpenBSD and so on.
Each of these operating systems is competent and production ready, each has it strengths and weaknesses, each has its unique technologies and goals. So the question is why has Linux won the popularity context.

Using a tool like Google Trends it is clear that searches and news stories for Linux are more than 20 times higher than that of FreeBSD or OpenSolaris. The question is why?

The answer can be summed up in two words: license and hero. In this case the license is the GPL and the hero is Linus Torvalds.

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