What tag is used to define a header in HTML?

The tag used to define a header in HTML is the

tag. This semantic element is specifically designed to contain introductory content or navigational links for a section or the entire webpage. It can encompass various elements, such as headings, logos, navigation bars, and other introductory material.

Using the

tag provides better structure to a webpage and improves accessibility, as screen readers and browsers can distinguish this section as containing important introductory content. The

element also allows for a clearer organization of the website, facilitating easier updates and maintenance.

Other choices refer to different aspects of HTML. The tag is used to contain metadata and links to stylesheets or scripts, while the

tag is used to define the highest-level heading within a section of content, not a complete header structure. The term is actually not a valid HTML tag at all. Hence,

is the best choice for defining a header in HTML.