is the fundamental language of the web. Using so-called tags, it describes the structure of a page, for example headings, paragraphs, lists, links and images. An image is embedded with the <img> tag, a link with <a href>.

For search engines and crawlers, HTML is especially important because it forms the directly readable basis of a page. Content already present in the initial HTML is captured more robustly than content created only by JavaScript.

Key elements are provided via HTML:

  • the and the ,
  • headings such as , H2 and H3,
  • real with the href attribute,
  • the alt attribute for images.

HTML is often combined with for layout and JavaScript for .