The kernel of MacOS on the other hand is based on (Free)BSD, another open source operating system ...
But why has Windows this huge market share? Because if one buys a computer Windows is pre-installed. So if Dell, HP and all others would install Linux, I think the market share of Windows would decrease rapidly.
Now, back to my first sentence. If Linux would ever gain a market share above 50%, I'll use FreeBSD.
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