Much of the information on U.S. industries and businesses is organized by two major industry classification systems: the North American Industry Classification System (NAICS) and the Standard Industry Classification System (SIC). Both are hierarchical, numerical classification systems. Internationally-focused sources often apply other industry classification systems.
Companies engaged in a wide range of activities may have multiple industry classifications, although usually one industry is considered primary.
The classification systems themselves do not provide direct links to industry information but many online databases and print directories enable searching by these codes. The systems also provide useful descriptions of industries and sub-industries as well as inspiration for search terms.
Print: Tisch Reference and Ginn Reference HF1042 .N67 (older editions in the stacks)
Pronounced ‘nakes’, 6-digit classification system focusing on business activities and production processes. Developed jointly by the U.S., Canada, and Mexico to provide comparable business statistics throughout North America. Businesses using similar production processes are grouped together.
4-digit classification system focusing on manufactured goods and their constituent materials. Developed in the 1930s by the U.S. Central Statistical Board, superseded by NAICS and has not updated since 1987, although many sources such as the U.S. Department of Labor still apply it.
3-5 digit classification system for products produced by service industries in 12 NAICS sectors in the 48-49 through 81 divisions. Is a complement to NAICS and organizes products primarily by their use. Implementation started in 2007.
10-digit classification system developed by MSCI and Standard & Poor’s (S&P) to provide a system that would account for the increasing globalization of industry. Used primarily for finance and investment applications.