AEO content demarcation: separating main content from chrome
AI engines parse pages to extract just the main content, ignoring navigation, sidebars, ads, and footers. Pages that explicitly mark their main content with <main> and <article> get cleaner extraction — and consequently more accurate citations.
AI engines parse pages to extract just the main content, ignoring navigation, sidebars, ads, and footers. Pages that explicitly mark their main content with <main> and <article> get cleaner extraction — and consequently more accurate citations. Content demarcation is using semantic HTML to mark which part of the page is the primary content. <main> wraps the page's main area; <article> wraps a self-contained piece (a blog post); <aside> wraps secondary content (a sidebar callout). AI engines and screen readers both lean on these landmarks.
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What it is
Content demarcation is using semantic HTML to mark which part of the page is the primary content. <main> wraps the page's main area; <article> wraps a self-contained piece (a blog post); <aside> wraps secondary content (a sidebar callout). AI engines and screen readers both lean on these landmarks.
Why it matters
Without clear demarcation, AI engines may extract sidebar quotes as part of the main answer, or skip relevant content thinking it's chrome. Citation snippets become noisier; the page is less likely to be chosen.
How to fix it
- Wrap article body in <article>. For blog posts, news, case studies — anything that is a self-contained piece. The H1 of the article goes inside.
- Use <main> for the page's primary content. One per page. Everything between header/nav and footer.
- Use <aside> for callouts and sidebars. Anything tangentially related to the main content. Engines learn to skip these.
Authoritative sources
- Google Search Central documentation — Google
- Schema.org vocabulary — schema.org
- SEO Starter Guide — Google Search Central
- MDN — HTML meta and link elements — Mozilla MDN