Research classification

The OECD Fields of Science and Technology Classification is a two levels classification, that is incorporated in Frascati Manual, in other words the OECD Proposed Standard Practice for Surveys of Research and Experimental Development. According to OECD, approach for defining two-level fields is also used, with the possibility for supplementation of third-level classification within those fields;

The European Economic Community Sciences Classification (EEC) is a three levels classification that is used by certain number of countries – member states of the European Union;

The US National Science Foundation Classification ( NSF) is a two levels classification, that is used in the USA.