There are three main sources for industry information:
Industry classification systems are created to promote data comparability. NAICS (current version) and SIC (older version) are the most widely used in the United States. You can search by codes to find information on industries or sectors in many databases and government websites. However, NAICS and SIC focus on broader industry activities and may not have a specific code for niche/emerging industries.
Standard used by Federal statistical agencies in classifying business establishments for the purpose of collecting, analyzing, and publishing statistical data related to the U.S. business economy. Updated every 5 years.
Older system (doesn't cover industries that emerged after 1987).
An industry association is established to advocate for the industry and associated companies. They collect and provide unique data/articles/reports. Sometimes these sources are on their websites for free.
To find the industry association websites:
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