1. 4.3 Sections
      1. 4.3.1 The body element
      2. 4.3.2 The article element
      3. 4.3.3 The section element
      4. 4.3.4 The nav element
      5. 4.3.5 The aside element
      6. 4.3.6 The h1, h2, h3, h4, h5, and h6 elements
      7. 4.3.7 The hgroup element
      8. 4.3.8 The header element
      9. 4.3.9 The footer element
      10. 4.3.10 The address element
      11. 4.3.11 Headings and outlines
        1. 4.3.11.1 Heading levels & offsets
        2. 4.3.11.2 Sample outlines
        3. 4.3.11.3 Exposing outlines to users
      12. 4.3.12 Usage summary
        1. 4.3.12.1 Article or section?

4.3 Sections

Introduction_to_HTML/Document_and_website_structure#HTML_for_structuring_content

Support in all current engines.

Firefox4+Safari5+Chrome5+
Opera11.1+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android11.1+

4.3.1 The body element

Element/body

Support in all current engines.

Firefox1+Safari1+Chrome1+
Opera?Edge79+
Edge (Legacy)12+Internet ExplorerYes
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android?

HTMLBodyElement

Support in all current engines.

Firefox1+Safari3+Chrome1+
Opera12.1+Edge79+
Edge (Legacy)12+Internet Explorer4+
Firefox Android?Safari iOS1+Chrome Android?WebView Android?Samsung Internet?Opera Android12.1+
Categories:
None.
Contexts in which this element can be used:
As the second element in an html element.
Content model:
Flow content.
Tag omission in text/html:
A body element's start tag can be omitted if the element is empty, or if the first thing inside the body element is not ASCII whitespace or a comment, except if the first thing inside the body element is a meta, noscript, link, script, style, or template element.
A body element's end tag can be omitted if the body element is not immediately followed by a comment.
Content attributes:
Global attributes
onafterprint
onbeforeprint
onbeforeunload
onhashchange
onlanguagechange
onmessage
onmessageerror
onoffline
ononline
onpageswap
onpagehide
onpagereveal
onpageshow
onpopstate
onrejectionhandled
onstorage
onunhandledrejection
onunload
Accessibility considerations:
For authors.
For implementers.
DOM interface:
[Exposed=Window]
interface HTMLBodyElement : HTMLElement {
  [HTMLConstructor] constructor();

  // also has obsolete members
};

HTMLBodyElement includes WindowEventHandlers;

The body element represents the contents of the document.

In conforming documents, there is only one body element. The document.body IDL attribute provides scripts with easy access to a document's body element.

Some DOM operations (for example, parts of the drag and drop model) are defined in terms of "the body element". This refers to a particular element in the DOM, as per the definition of the term, and not any arbitrary body element.

The body element exposes as event handler content attributes a number of the event handlers of the Window object. It also mirrors their event handler IDL attributes.

The event handlers of the Window object named by the Window-reflecting body element event handler set, exposed on the body element, replace the generic event handlers with the same names normally supported by HTML elements.

Thus, for example, a bubbling error event dispatched on a child of the body element of a Document would first trigger the onerror event handler content attributes of that element, then that of the root html element, and only then would it trigger the onerror event handler content attribute on the body element. This is because the event would bubble from the target, to the body, to the html, to the Document, to the Window, and the event handler on the body is watching the Window not the body. A regular event listener attached to the body using addEventListener(), however, would be run when the event bubbled through the body and not when it reaches the Window object.

This page updates an indicator to show whether or not the user is online:

<!DOCTYPE HTML>
<html lang="en">
 <head>
  <title>Online or offline?</title>
  <script>
   function update(online) {
     document.getElementById('status').textContent =
       online ? 'Online' : 'Offline';
   }
  </script>
 </head>
 <body ononline="update(true)"
       onoffline="update(false)"
       onload="update(navigator.onLine)">
  <p>You are: <span id="status">(Unknown)</span></p>
 </body>
</html>

4.3.2 The article element

Element/article

Support in all current engines.

Firefox4+Safari5+Chrome5+
Opera11.1+Edge79+
Edge (Legacy)12+Internet Explorer9+
Firefox Android?Safari iOS?Chrome Android?WebView Android?Samsung Internet?Opera Android11.1+
Categories:
Flow content.
Sectioning content.
Palpable content.
Contexts in which this element can be used:
Where sectioning content is expected.
Content model:
Flow content.
Tag omission in text/html:
Neither tag is omissible.
Content attributes:
Global attributes
Accessibility considerations:
For authors.
For implementers.
DOM interface:
Uses HTMLElement.

The article element represents a complete, or self-contained, composition in a document, page, application, or site and that is, in principle, independently distributable or reusable, e.g. in syndication. This could be a forum post, a magazine or newspaper article, a blog entry, a user-submitted comment, an interactive widget or gadget, or any other independent item of content.

When article elements are nested, the inner article elements represent articles that are in principle related to the contents of the outer article. For instance, a blog entry on a site that accepts user-submitted comments could represent the comments as article elements nested within the article element for the blog entry.

Author information associated with an article element (q.v. the address element) does not apply to nested article elements.

When used specifically with content to be redistributed in syndication, the article element is similar in purpose to the entry element in Atom. [ATOM]

The schema.org microdata vocabulary can be used to provide the publication date for an article element, using one of the CreativeWork subtypes.

When the main content of the page (i.e. excluding footers, headers, navigation blocks, and sidebars) is all one single self-contained composition, that content may be marked with an article, but it is technically redundant in that case (since it's self-evident that the page is a single composition, as it is a single document).

This example shows a blog post using the article element, with some schema.org annotations:

<article itemscope itemtype=&quot;https://www.downtownmelody.com/_x/c2NoZW1hLm9yZw/BlogPosting&quot;>
 <header>
  <h2 itemprop="headline">The Very First Rule of Life</h2>
  <p><time itemprop="datePublished" datetime="2009-10-09">3 days ago</time></p>
  <link itemprop="url" href="?comments=0">
 </header>
 <p>If there's a microphone anywhere near you, assume it's hot and
 sending whatever you're saying to the world. Seriously.</p>
 <p>...</p>
 <footer>
  <a itemprop="discussionUrl" href="?comments=1">Show comments...</a>
 </footer>
</article>

Here is that same blog post, but showing some of the comments:

<article itemscope itemtype=&quot;https://www.downtownmelody.com/_x/c2NoZW1hLm9yZw/BlogPosting&quot;>
 <header>
  <h2 itemprop="headline">The Very First Rule of Life</h2>
  <p><time itemprop="datePublished" datetime="2009-10-09">3 days ago</time></p>
  <link itemprop="url" href="?comments=0">
 </header>
 <p>If there's a microphone anywhere near you, assume it's hot and
 sending whatever you're saying to the world. Seriously.</p>
 <p>...</p>
 <section>
  <h1>Comments</h1>
  <article itemprop="comment" itemscope itemtype=&quot;https://www.downtownmelody.com/_x/c2NoZW1hLm9yZw/Comment&quot; id="c1">
   <link itemprop="url" href="#c1">
   <footer>
    <p>Posted by: <span itemprop="creator" itemscope itemtype=&quot;https://www.downtownmelody.com/_x/c2NoZW1hLm9yZw/Person&quot;>
     <span itemprop="name">George Washington</span>
    </span></p>
    <p><time itemprop="dateCreated" datetime="2009-10-10">15 minutes ago</time></p>
   </footer>
   <p>Yeah! Especially when talking about your lobbyist friends!</p>
  </article>
  <article itemprop="comment" itemscope itemtype=&quot;https://www.downtownmelody.com/_x/c2NoZW1hLm9yZw/Comment&quot; id="c2">
   <link itemprop="url" href="#c2">
   <footer>
    <p>Posted by: <span itemprop="creator" itemscope itemtype=&quot;https://www.downtownmelody.com/_x/c2NoZW1hLm9yZw/Person&quot;>
     <span itemprop="name">George Hammond</span>
    </span></p>
    <p><time itemprop="dateCreated" datetime="2009-10-10">5 minutes ago</time></p>
   </footer>
   <p>Hey, you have the same first name as me.</p>
  </article>
 </section>
</article>

Notice the use of footer to give the information for each comment (such as who wrote it and when): the footer element can appear at the start of its section when appropriate, such as in this case. (Using header in this case wouldn't be wrong either; it's mostly a matter of authoring preference.)

In this example,