Unix or Linux

Un post con mucha inforamción sobre sistemas operativos, características y comparaciones.
https://www.digitalocean.com/community/tutorials/a-comparative-introduction-to-freebsd-for-linux-users

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https://www.digitalocean.com/community/tutorials/a-comparative-introduction-to-freebsd-for-linux-users
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Algunas ideas, mientras que GNU/Linux apunta a ser y perpetuarse como algo cooperativo.
Las versiones derivadas de UNIX admiten el fin comercial sin forzar a seguir siendo cooperativos.
Esto que parece algo "trivial", ocasiona que OSX esté basado en BSD para poder comercializarse (OSX) mientras que BSD es gratuito.
Si no estuviera BSD, se debería haber hecho un S.O. desde cero para OSX o se debería haber usado Linux, lo que hubiera significado menos beneficios comerciales para Apple.