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An HTML entity is a piece of text ("string") that begins with the ampersand (&) character and ends with the semicolon (;) character.  Often, users employ entities to display characters that are normally interpreted as HTML code, invisible characters such as the non-breaking space, or characters that are difficult to type with a standard keyboard. 

Many characters have memorable entities. For example, the entity for the copyright symbol (©) is ©. For characters that don't have a memorable entity, you can use a numeric character reference, such as — or —. To get the numeric character reference, you can use a tool.

HTML reserves four characters for its syntax:

&
the ampersand
<
the less-than sign
>
the greater-than sign
"
the straight double-quote character

Instead of displaying these characters as text, browsers interpret them according to special rules, or "parse" them. For instance, if you use the less-than (<) sign in HTML, the browser interprets the following text as a tag. To display the characters as text, known as "escaping" the characters, replace them with their corresponding character entities in the following table.

Character Entity Note
& &amp; Interpreted as the beginning of an entity or character reference.
< &lt; Interpreted as the beginning of a tag
> &gt; Interpreted as the ending of a tag
" &quot; Interpreted as the beginning and end of an attribute's value.

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 Last updated by: rolfedh,