Why is semantic HTML important and what are common semantic elements?

Semantic HTML uses elements that describe meaning, not just appearance. **Why it matters:** - Better accessibility (screen readers understand structure) - Better SEO (clear page hierarchy) - More maintainable markup **Common semantic elements:** `header`, `nav`, `main`, `section`, `article`, `aside`, `footer`, `figure`, `time`, and proper heading order (`h1`–`h6`). **Interview tip:** mention that semantics + accessibility often improve SEO indirectly because search engines can better interpret content structure.