The North American Industry Classification code system is developed and maintained by the US Census Bureau as a way to classify the industry for physical business locations operating in Canada, Mexico and the United States. This allows all the agencies collecting industry data on the US economy to have a consistent reporting field for industry metrics, enabling comparison between different data sets. NAICS codes are always six digits, with the first two digits being designating the largest industry sector and the full six digits identifying the most detailed industry level.
The NAICS codes not only provide a consistent framework for industry classification that aids in statistical descriptions of employers, but also entities such as state governments and contracting authorities may offer incentives to businesses with specific NAICS codes or require certain codes to qualify for contracting.
At Ididio, we generally use NAICS codes at the broad sector level in tandem with SOC codes to provide insight of differences in careers across industries.
We are currently using the 2012 NAICS codes and definitions. Those along with the more recent 2017 definitions are available at the NAICS downloadable files site.