Something about diacritics and other abnormal letters

REF:
http://www.wesleyan.edu/CTWMellon/Resources/Quickstarts/fchtml.html
http://lynx.isc.org/release/lynx2-8-4/test/iso88592.html
http://www.lib.washington.edu/help/catalog/Diacritics.html
http://www.les.aston.ac.uk/chars.html
etc.

The problem comes out from sometimes though very rare we need those letters e.g. ö, õ. This kind of letters namely Diacritics. After some little research, I found the methods to show those letters. For html,
acute Á Á
circumflex  Â
grave À À
tilde à Ã
umlaut Ä Ä
cedilla Ç Ç
sz ß ß
slash ø ø
breve ă :(
ae æ æ
ampersand & &
ð

to be finished...