What is schema markup?
Schema markup is structured data you add to your HTML to help search engines understand your content. It uses the Schema.org vocabulary — a standardized set of types and properties that describe entities like articles, products, events, FAQs, organizations, and people.
Implementation: use JSON-LD (JavaScript Object Notation for Linked Data), which is Google's recommended format. Add a `<script type="application/ld+json">` block in your page's `<head>` or `<body>` with the structured data.
Most impactful schema types for business sites: Organization (your company details, logo, contact), Article (blog posts with author, date, word count), FAQPage (questions and answers — triggers rich snippets in search results), BreadcrumbList (navigation path — appears in search results), HowTo (step-by-step guides), Product (with price, availability, reviews), and LocalBusiness (for location-based businesses).
Schema doesn't directly improve rankings, but it enables rich snippets — enhanced search result displays with star ratings, FAQ accordions, prices, and images. Rich snippets increase click-through rates by 20-30%, which indirectly improves rankings through better engagement signals.
Validation: use Google's Rich Results Test (search.google.com/test/rich-results) and Schema.org's validator. Test every new schema addition — malformed JSON-LD is silently ignored, so you won't know it's broken without testing.