How quickly a particular page loads useful content and responds during a visit.
A practical example
A team investigates an oversized hero image delaying the main content on mobile connections.
What to watch for
A single lab score is not the full experience. Combine diagnostics with real-user loading, interaction and layout-stability evidence.
Related reading
Explore Site Speed and JavaScript. Try our noindex checker for a practical next step. See how this fits into Technical SEO.