HTML Entities:
Some characters are reserved in HTML.
If you use the less than (<) or greater than (>) signs in your text, the browser might mix them with tags.
Character entities are used to display reserved characters in HTML.
A character entity looks like this:
&entity_name;
OR
&#entity_number;
Many mathematical, technical, and currency symbols, are not present on a normal keyboard.
To add such symbols to an HTML page, you can use the entity name or the entity number (a decimal or a hexadecimal reference) for the symbol.
Example
Display the euro sign, €, with an entity name, a decimal, and a hexadecimal value:<p>I will display €</p>
<p>I will display €</p>
<p>I will display €</p>
<p>I will display €</p>
display:
I will display €
I will display €
I will display €