What OKI calls "Types" are crucial to the interoperability of the OSIDs. The OSIDs themselves are written very generically. It is only through a common understanding of the out-of-band "Types" that applications can make use of the most important functionality. For example, the seach methods in the Repository OSID require a Search Type. It is only by defining a commonly understood set of Search Types that different repositories can be searched in the same way.

The Types themselves are not part of the OKI specification per se; they are expected to be developed by the community as implementations are created. Implementors of OSIDs are strongly encouraged to submit their Types to the community at large.

See OSID V3 Type Package ? for latest on developments