Entitycode is a website that provides the web service of letting you have some special symbols that you cannot type through your keyboard. These special characters can be easily added now using this web site. It basically has a collection of all html entities and more.
Entities are used to implement reserved characters or to express characters that cannot easily be entered with the keyboard. ISO-8859-1 is the default character set in most browsers. The first 128 characters of ISO-8859-1 is the original ASCII character-set (the numbers from 0-9, the uppercase and lowercase English alphabet, and some special characters).
The higher part of ISO-8859-1 (codes from 160-255) contains the characters used in Western European countries and some commonly used special characters. The HTML Symbol Entities include mathematical symbols, Greek characters, various arrows, technical symbols and shapes. It is worth noting that Entity Names are case sensitive.