16-00 General reference works (handbooks, dictionaries, bibliographies, etc.)
16-01 Instructional exposition (textbooks, tutorial papers, etc.)
16-02 Research exposition (monographs, survey articles)
16-03 Historical (must also be assigned at least one classification number from Section 01)
16-04 Explicit machine computation and programs (not the theory of computation or programming)
16-06 Proceedings, conferences, collections, etc.
16Bxx General and miscellaneous
16Dxx Modules, bimodules and ideals
16Exx Homological methods {For commutative rings, see 13Dxx; for general categories, see 18Gxx}
16Gxx Representation theory of rings and algebras
16H05 Orders and arithmetic, separable algebras, Azumaya algebras [See also 11R52, 11R54, 11S45]
16Kxx Division rings and semisimple Artin rings [See also 12E15, 15A30]
16Lxx Local rings and generalizations
16Nxx Radicals and radical properties of rings
16Pxx Chain conditions, growth conditions, and other forms of finiteness
16Rxx Rings with polynomial identity
16Sxx Rings and algebras arising under various constructions
16Uxx Conditions on elements
16Wxx Rings and algebras with additional structure
16Yxx Generalizations {For nonassociative rings, see 17-XX}
16Z05 Computational aspects of associative rings [See also 68W30]