Character Encoding in general

[Thomas]

Hi there,

I feel really dizzy now. I really need someone to enlighten me now. I 
used to set some character encoding settings to mount my vfat partition, 
to communicate via putty, and even while coding java to write to a file 
stream. Still, i have not the slightest clue what  "UTF-8", 
"ISO-8859-1", "CP12??" etc. means. The only thing i notice, is that 
special chars dont work if i set it wrong, and copying a binary file 
will fail if i dont use the right settings. But what the heck IS 
character encoding? What does that mean? Is is operating system 
dependent? Is it file system dependent? Is it Manufacturer dependent? 
Why does it never work by default when putting different OS (Like Win98, 
XP, Linux) together? Has it always something to do with streams?

Now here comes my real question:
Can anyone pls recommend a good reading on the web that will really 
explain what it is, not just what i have to set to make something work?

Thanx a lot.

Thomas