What is an non empty tag?

A non-empty tag is an HTML or XML element that contains content between its opening and closing tags. For example, in the tag <p>This is a paragraph.</p>, both the opening <p> and closing </p> tags are present, and the content "This is a paragraph." makes it non-empty. In contrast, an empty tag, like <br>, does not contain any content between the tags. Non-empty tags are essential for structuring and organizing content in web documents.