Structured data describes your page in a format search engines read directly. Some types produce visible enhancements; most produce nothing visible and still help machines understand what you are. Both are worth having, for different reasons.
Types that produce something visible
| Type | What appears | Who it suits |
|---|---|---|
| Product | Price, availability, ratings in results | Any store |
| FAQPage | Expandable questions under the result | Service and support pages |
| BreadcrumbList | A readable path instead of a raw URL | Every site with sections |
| Recipe / Event / JobPosting | Rich cards and dedicated surfaces | Those specific verticals |
| LocalBusiness | Map and business panel eligibility | Anyone with a location |
Types worth having with nothing visible
- Organization. How a search engine connects your name to your site as an entity. Important when your name is not unique.
- WebSite. Establishes the site name used in results.
- Article. Attribution and dates, and increasingly how AI assistants attribute a source.
- Service. Makes what you sell machine-readable, which matters as assistants answer recommendation questions.
The mistakes that get it ignored
- 01Marking up content that is not on the page. The single fastest way to a manual action.
- 02Ratings without visible reviews. Review markup requires the reviews to be present on the same page. This is enforced.
- 03Marking up every page as the same thing. A category page is not a Product.
- 04Leaving stale data. A Product marked in stock that is not undermines trust in all of your markup.
- 05Multiple conflicting blocks. Two Organization definitions with different names is worse than one.
One technical detail worth knowing
JSON-LD embedded in a page must be escaped for HTML, not only serialised as JSON. Serialising alone leaves angle brackets intact, so any content containing a closing script tag ends the block early and the rest is parsed as markup. That is a cross-site scripting hole delivered through your structured data.
It is rare, because most markup comes from trusted fields. It stops being rare the moment any of it is user-generated or drawn from a CMS.
How to check
Google's Rich Results Test tells you what is eligible; the Schema.org validator tells you what is valid. They answer different questions and both are worth running. After that, Search Console reports errors on live pages, which is the only view that reflects reality.
Working on something like this?
We build websites, stores and custom applications, and we will tell you honestly if the thing you are describing does not need one.