Entities

Entities are character sequences placed in the text of an HTML document to print out reserved characters which may otherwise be interpreted as HTML code by a browser, or other special characters that would be difficult to generate with a typical keyboard. In fact, using reference numbers, an entity can represent any Unicode character. When parsing the HTML, a browser replaces the entity’s character sequence with the character it represents.

Syntax

Entities are case-sensitive and can take one of three forms.

The first form references an entity by name:

&name;

The second form references it by the decimal Unicode number:

&#number;

The third represents it with the hexadecimal Unicode number, often with leading zeros:

&#xnumber;

So the copyright entity (©) can be represented as ©, &#169 or ©.

Entity Values

There are many HTML entities. The following are some common ones:

More can be found in this extensive HTML 5 entity reference.

The Tab Entity

There is an entity 	 (or 	) which nominally produces a tab character. However, it will not behave as expected because HTML collapses whitespace where it appears in text with the exception of the non-breaking space entity,  . So to render a tab in HTML text, it needs to be wrapped within a <pre> tag to preserve the whitespace.

<p>The tab entity &Tab; in this sentence is collapsed</p>

<pre>
  <p>The Tab entity &Tab; in this sentence is preserved</p>
</pre>

Alternatively, four   entities can be used.

<p>The Tab entity &Tab; in this sentence is collapsed.</p>

<p>The spaces &nbsp;&nbsp;&nbsp;&nbsp; in this sentence are preserved.</p>