NAICS-(pronounced like it rhymes with snakes) North American Industry Classification Codes were developed jointly by the US, Canada and Mexico in 1997 (and updated in 2002) and were intended to supercede the 1987 Standard Industrial Classification System. Used to classify the area in which a company operates.
A full list of the current NAICS codes can be found here: https://www.census.gov/eos/www/naics/.
SIC-Standard Industrial Classification, used to classify the area in which a company operates.
A full listing of SIC codes can be found here: https://www.osha.gov/pls/imis/sic_manual.html.
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