NAICS, North American Industry Classification System, is a five to six digit number created by the government to describe a business based on what it produces and how it produces it. Many companies have more than one NAICS code. Apple, for example, has three different codes: 33419 other electronic component manufacturing, 33410 semiconductor and other electronic component manufacturing, and 443143 appliance, television and other electronics stores.
The government routinely revises and updates NAICS codes. The most recent version was published in 2017.
There are several advantages to doing a search using a NAICS code.