HTML5 Empty or Void elements


Most of the HTML elements have a start and an end tag that indicate where the element begins and where it ends. There is a group of elements that don’t have end tags. These elements are called empty or void and only have a start tag since they can't have any content. They must not have an end tag in HTML.

So, to summarize:
  • An empty element is one that has no content, regardless of whether it is allowed to have content in the first place.
  • A void element is one that cannot have any content.

The void elements in HTML 4.01/XHTML 1.0 Strict are as follows:
<area>
<base>
<br>
<col>
<hr>
<input>
<link>
<meta>
<param>
<img>


 HTML5 currently adds:
<command>
<keygen>
<source>

To create a button with the input element, do this if you use an XHTML doctype:



    <input type="submit" value="Ok" />

And this for HTML:



    <input type="submit" value="Ok" />

Both are valid if you use HTML5.
Do not use end tag:



    <input type="submit" value="Ok" /> &lt;!&#8212; Not valid! --&gt;