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Proprietary (or Non-free) is anything that is under a restrictive license. This term can be used by both the Free Software Foundation followers, and members of the Open Source community for a vague term. For a more precise term, both fields of thought use their own concrete definitions. The Free Software Foundation followers use the term Non-free, while members of the Open Source community use the term Closed-Sourced. Both non-free and closed-source have similar, yet different meanings. Both terms, however, can be replaced with Proprietary when being general.