The <aside> element represents a portion of a document whose content is only indirectly related to the document's main content.

The <base> element sets the base URL (the URL that relative URLs are relative to) for all relative URLs in the document.

The <blockquote> element represents an extended quotation, styling contents as an indented block by default.

The <body> element represents the content of an HTML document.

The <br> element produces line breaks in text.

The <code> element displays its contents as a fragment of computer code.

The <dfn> element marks a term to be defined, styling text as italic by default.

The <figure> and <figcaption> HTML elements represent an illustration, diagram, text, or other self-contained reference content, with an optional caption.

The <head> element contains machine-readable information (metadata) about the document, such as the title, <script> and <style> elements, and <meta> elements.

The <header> and <footer> HTML elements represent content that precedes and follows the main page content, respectively.

The <hgroup> element represents a heading and related content.

The <hr> element represents a thematic break between paragraphs, often shown as a horizontal rule.

The <html> element represents the top-level of an HTML document and is referred to as the root element.

The <i> HTML element identifies idiomatic content, styling text as italic by default.

The <main> element represents the dominant content of a document. It is commonly used together with <header> and <footer>.

The <mark> element represents text which is marked or highlighted for reference or notation purposes.

The <p> element represents a paragraph of text.

The <q> element represents a short inline quotation.

The <ruby> element produces small annotations that are rendered with its base text.

The <span> HTML element is the generic inline container for content.

The <sub> and <sup> elements sets inline text to be displayed as subscript or superscript for solely typographical reasons.

The <var> element represents the name of a variable in a mathematical expression or a programming context.

The sandbox attribute for the <iframe> HTML element sets many security restrictions on the iframe, such as preventing form submissions or opening modal dialogs. Optional allow- values relax specific restrictions.

The <table> HTML element, with several related elements, represents tabular data in rows and columns of cells.