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"By 'open access'... we mean it's freely available on the public internet, permitting any users to read, download, copy, distribute, print, search or link to the full text of these articles, crawl them for indexing, pass them as data to software or use them for any other lawful purpose…" (The Budapest Open Access Initiative).
The term Open Access describes the nature of access, rather than a specific business model, licence or type of content.