Entity Code - A Clear and Quick Reference to HTML Entities Codes
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EntityCode A Clear and Quick Reference to HTML Symbol Entities Codes

Codes for HTML symbols

Decent reference.

"Some characters (e.g. the less than and greater than signs) are reserved for HTML markup. In order to display these characters as text, you must enter the HTML entities in the source code. For example, to display the less than sign (<), you need to enter &lt; (entity name) or &#60; (entity number). Among the entity list, there are quite a lot of symbol entities that we can use in layout design. For examples: → ♥ ♫ ✓ ✗ • ☞ ✁ ★ “ ⊕. Have you seen the snowman ☃ symbol before? If not, continue on this post to find more surprises."

Quick references of most common XHTML entities.

Quick References of Most Common Entities