"Unprintable" 8-bit characters

[David Brodbeck]

It's worth noting, too, that most of the non-Unicode encoding systems
predate the Internet.  When computers weren't really talking to each
other, there was no real emphasis on interoperability, and every OS
tended to come up with their own way of encoding foreign languages.
Languages like French, German, and English generally have it easy --
almost everything ended up being Latin1 (aka ISO 8859-1).  For other
languages it can be much more complicated.  There are at least three
commonly used encoding systems for Chinese.  Unicode is gradually
winning, but you'll still find, for example, a lot of Chinese
documents in GB2312 and Big5.