Using a site structure analysis tool can help identify areas of your website that need improvement, resulting in a more user-friendly experience for your audience. HTML provides the primary site-built structure and content of a web page, including headings, paragraphs, links, and images. Using HTML, you can create a well-structured website that is easy to navigate and understand. By separating the presentation from the content, CSS allows you to make changes to the appearance of your site without affecting its optimized site structure.