An SEO audit analyzes a website's on-page elements, off-page links, technical performance, and site structure to identify issues impacting search engine optimization and recommendations for improvement. The on-page analysis examines factors like meta tags, header tags, URL structure, and image alt text. Off-page analysis evaluates backlinks, page rank, domain authority, and page authority. Technical performance is assessed through robots.txt, sitemaps, and page speed. Proper site structure with hierarchical categorization helps search engines index content and provides a better user experience.