Schema markup

Schema markup (using Schema.org vocabulary) is JSON-LD you add to a page's <head> to describe its content — Article, Product, Review, FAQPage, BreadcrumbList, SoftwareApplication, DefinedTerm, and dozens more types. Search engines use schema to build rich results: star ratings, FAQ dropdowns, breadcrumbs, price chips, and sitelinks search boxes. It doesn't directly rank pages higher, but it's the biggest lever for click-through-rate improvement because rich results consume more SERP real estate than a plain blue link. A typical implementation: global layout emits WebSite + Organization; article pages emit Article + BreadcrumbList; product or SaaS tool pages emit SoftwareApplication + AggregateRating; FAQ sections emit FAQPage. Validation: use Google's Rich Results Test (search.google.com/test/rich-results) before deploying. The most common mistakes are using incorrect property types, omitting required fields, and using schema that misrepresents the page content — all of which can trigger manual actions.