Many business databases can be searched by NAICS or SIC code. Searching with these codes can help narrow in on sources about a particular industry.
The North American Industry Classification System (NAICS) is the 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. The NAICS system was meant to relace an older system called SIC (Standard Industrial Classification).
To identify a NAICS code, search for an industry or company in one of these sources: