What it is
Structured data is a short block of code (JSON-LD) in your page that states facts about your business in a standard format from schema.org.
The minimum
Use the most specific type you can (Plumber, Dentist, Restaurant), with name, address, telephone, opening hours, URL and logo.
Keep it consistent
The same name, address and phone as on your page and your Google Business Profile.
What to expect
It makes your details unambiguous and can enable rich results. It doesn't guarantee a ranking or a mention.
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