Most people will agree on what a commercial distro is. it is fairly obvious. A distro that is funded and backed by a company.
Examples would be Suse, RedHat, Mandriva, and others. Some of these making more money than others.
Then there is the wild west world of "Community" distros.
It is an interesting place this Community world. It contains distros that stretch the very boundaries on either end of the scale.
For example, on one end, there is Ubuntu. It pushes itself as a community distro although it is financially backed by a company, Canonical, and does pay some developers to contribute and maintain it. it is not sold to the public in any form and does not generate revenue, unlike the 'full' commercial distros mentioned above.
Ubuntu is released on fixed schedules and the repos are available to support those releases for a fixed time.
Ubuntu is based on another distro, that ironically, perhaps best encompasses the entire opposite end of the spectrum that is Community. Debian.
Debian is about as "Community" as it gets.
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