Schema Markup

Schema markup is structured data added to a page that describes its content in a vocabulary search engines understand. The vocabulary, defined at Schema.org, is a joint project of Google, Bing, Yandex, and Yahoo. Adding schema does not directly improve rankings — Google has been clear about this — but it makes pages eligible for rich SERP features that improve click-through and visibility.

The recommended implementation format is JSON-LD, a JavaScript-flavoured JSON block placed in the page's head or body. JSON-LD is preferred over the older Microdata and RDFa formats because it is decoupled from the rendered HTML, easier to maintain, and easier to inject server-side from templates.

Common schema types that produce visible SERP enhancements: Article (article headlines and dates), Product (price, availability, rating stars), Recipe (ingredients, cook time, calorie counts), FAQPage (expandable Q&A in search results — though Google reduced this feature's visibility in 2023), HowTo (step-by-step instructions), BreadcrumbList (Breadcrumb in the SERP), Organization (logo and social profiles in the Knowledge Graph), and DefinedTerm (glossary entries like the ones on this site).

Implementation discipline matters. Schema must accurately reflect what is on the page — marking up a price that does not exist, a rating with no underlying review system, or an event with fake dates is against Google's structured data guidelines and can result in manual actions revoking rich result eligibility for the entire site. Test markup with Google's Rich Results Test before deploying, and monitor the Enhancements reports in Search Console for ongoing validation errors.

Schema is also one of the strongest signals for E-E-A-T when applied properly. Marking up authorship with Person schema, linking to verifiable author bios, and connecting Organization schema to social profiles helps Google build a coherent picture of the entities behind your content.

For most modern sites, the baseline schema set is: WebSite (with potentialAction for sitelinks search box), Organization (with logo and social profiles), BreadcrumbList on every non-homepage URL, and content-type-specific schema (Article, Product, etc.) wherever applicable. Add specialised types only where they accurately describe the content.