Terminology
Hybrid OA Journal seems to be the customary term, although OA by the article, optional oa and paid option for oa have also been used. Open choice, which properly means Springer's scheme, is sometimes used as the generic. From its originators, it has also been called the Walker–Prosser model for open-access journals.
Open access may be defined differently by different publishers. Open access involves more than free access. Permission barriers should also be minimized. For example, there are various versions of Creative Commons licenses. The most restrictive of the six main Creative Commons licenses allows anyone to download authors' works and share them with others, provided that the works are properly attributed and linked back to the original authors, and also provided that the works aren't changed in any way, nor used commercially. Other licenses are more accommodating.
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