Character Entities References are the way you put special letters, numbers and symbols on the web page. A character entity reference consists of an ampersand (&), followed by a pound sign (#), the number of the character entity, and finishing with a semi-colon (;). Alternately, for some characters you can put ampersand, the name of the character (but no # sign), followed by a semi-colon.
The following table shows some popular symbols :
| 34 | quot | “ | quotation mark = APL quote |
| 38 | amp | & | ampersand |
| 60 | lt | < | less-than sign |
| 62 | gt | > | greater-than sign |
| 160 | nbsp | no-break space = non-breaking space | |
| 169 | copy | © | copyright sign |
| 174 | reg | ® | registered sign = registered trade mark sign |
| 8226 | bull | • | bullet = black small circle bullet is NOT the same as bullet operator |
Character entities or extended characters for WordPress are explained on the codex.wordpress.org website.