Here is a great article about Unicode and how it affects Web developers and programmers. Here’s an excerpt:
The Single Most Important Fact About Encodings
If you completely forget everything I just explained, please remember one extremely important fact. It does not make sense to have a string without knowing what encoding it uses. You can no longer stick your head in the sand and pretend that “plain” text is ASCII.
There Ain’t No Such Thing As Plain Text.
If you have a string, in memory, in a file, or in an email message, you have to know what encoding it is in or you cannot interpret it or display it to users correctly.
Almost every stupid “my website looks like gibberish” or “she can’t read my emails when I use accents” problem comes down to one naive programmer who didn’t understand the simple fact that if you don’t tell me whether a particular string is encoded using UTF-8 or ASCII or ISO 8859-1 (Latin 1) or Windows 1252 (Western European), you simply cannot display it correctly or even figure out where it ends. There are over a hundred encodings and above code point 127, all bets are off.
For the article, go to: http://www.joelonsoftware.com/articles/Unicode.html