Structured data is machine-readable markup — schema.org, embedded as JSON-LD — that tells search engines and AI assistants exactly who you are, what you sell, and what your pages mean. For marketers, four types carry most of the weight: Organization, Service, FAQPage, and Article. Everything else is polish.
Why a marketer should care about markup
Humans infer. A person lands on your site and pieces together what you do from the headline, the logo, the tone. Machines do not infer well, and increasingly it is machines deciding whether you get surfaced at all — in rich search results, and in the answers AI assistants give when a buyer asks who to hire.
Structured data is you filling out the machine’s form instead of hoping it guesses right. That is not a technical nicety. It is positioning, in the most literal sense the word has ever had.
The four types that matter
Organization (or its more specific cousins like ProfessionalService and LocalBusiness) is your entity record: name, founding date, location, founder, what you are. It should appear on every page and never contradict itself. This is the markup that lets an assistant state facts about your business instead of hedging.
Service markup enumerates what you actually sell. A site with a machine-readable service catalog gets described completely when someone asks an assistant what a company offers; a site without one gets a vague paraphrase or gets skipped for a competitor who did the work.
FAQPage marks up real questions with real answers — the exact question-and-answer shape assistants are built to lift. And Article, with a genuine author and publish date, tells machines your content is authored and current rather than anonymous and stale.
The mistakes that waste the effort
Broken JSON is the most common one — a stray quote or an HTML entity inside the markup, and the whole block silently parses to nothing. Present is not the bar; parseable is. Validate every block, every time you ship a change.
The second is contradiction. If your schema says one founding year, your about page another, and your directory listings a third, machines resolve the conflict by trusting you less on everything. Entity facts should be written once and echoed everywhere, identically.
The third is marking up things that do not exist — reviews you never collected, FAQs no one asked. Search engines penalize it, and it poisons the trust the rest of your markup earned.
How to start this week
Pick your entity facts and freeze them: legal name, founding year, location, what you are in one sentence. Ship Organization markup with exactly those facts on every page. Then add Service markup for each thing you sell, FAQ markup where you genuinely answer questions, and Article markup on anything with a byline.
Then validate all of it and re-validate whenever the site changes. In my experience the gap between sites that get cited and sites that get skipped is rarely brilliance — it is that one of them did the unglamorous work correctly.