Wiki stores text as UTF-8 Unicode characters. You can enter exotic characters using your computer's keyboard extension or by entering HTML entity codes.
If you see the character you want in another document, you may be able to simply copy and paste it into wiki. Try it. Otherwise consult the list of special Unicode characters available in your computer or on the web.
Caution: Page titles are converted to simplified names that do not contain any special characters when used as internal links.
Using Your Computer's Keyboard Extension
Apple Mac OS X Special Character Menu
The exact mechanism will vary with computers. We will describe using the Mac OS X and Chrome. Other systems will be similar.
While editing text, choose the menu option Edit > Special Characters ... This brings up the character menu keyboard extension. Choose to view Code Tables and Unicode within that. Select the letter you desire. Click Insert.
Using HTML Entities
You can add unusual characters to the text you type by typing the numerical code for the character you want. The code must be typed with HTML escape characters on either side. This is referred to as an HTML Entity.
If the character you wanted had unicode hexadecimal character number 2756 then you would type it as
& # x 2 7 5 6 ;
Unicode hexadecimal 2756 is a black diamond minus a white x. Here are three of them:
❖ ❖ ❖
You can find the HTML Entity code for many weird characters by consulting the internet.
Try graphemica.com. Use that site to search for black diamond. That will take you to a page that shows you many alternatives, one of which is the black diamond minus white x we used above.
Wiki's text editor will eventually convert HTML Entities into the characters themselves instead of the hexadecimal entity codes. Cut and past these at will. If things go wrong. Go back to entity codes.