HTML Entity Encode/Decode
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The HTML character encoder converts all applicable characters to their corresponding HTML entities. Certain characters have special significance in HTML and should be converted to their correct HTML entities to preserve their meanings.
For example, it is not possible to use the < character as it is used in the HTML syntax to create and close tags. It must be converted to its corresponding < HTML entity to be displayed in the content of an HTML page. HTML entity names are case sensitive.
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List of XML and HTML character entity references
In SGML, HTML and XML documents, the logical constructs known as character data and attribute values consist of sequences of characters, in which each character can manifest directly (representing itself), or can be represented by a series of characters called a character reference, of which there are two types: a numeric character reference and a character entity reference. This article lists the character entity references that are valid in HTML and XML documents.A character entity reference refers to the content of a named entity. An entity declaration is created by using the <!ENTITY name "value"> syntax in a Document Type Definition (DTD).
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