As the name indicates, these are tags that you can associate your business listing on Google with. Google allows you to pick a main category for your business and a bunch of additional categories. This has been created so that you can categorize your business in the best way possible.
Additional categories play an important role in map ranking Categories are used to describe your business and connect you to customers searching for the services you offer. For example, if your primary category is “Pizza restaurant”, Google may show your business in local search results to people who search for “Restaurants”, “Italian restaurants”, or “Pizza” in their area.