Industry codes group similar companies together in a way that helps researchers and government agencies collect and analyze information for that industry.
Prior to 1997, the United States used the 4-digit Standard Industrial Classification (SIC). It currently uses 6-digit North American Industry Classification System (NAICS).
International businesses are categorized by the International Standard Industrial Classification of All Economic Activities (ISIC) and/or the Standard International Trade Classification (SITC).
The following websites provide information about these classifications.
