When I compile my program as a native Unicode application, I believe
it stores all strings using double-byte characters.  Double-byte
implies 2 bytes.  UTF-8 supports byte sequences up to 6 bytes.  How
does Windows support this if they require only 2.  This would mean
that there are only 65,536 character possibilities... I thought some
languages had more than that.

Think Hexadecimal

One byte becomes two

Two bytes become four

You need to know whether the next byte is a new character if you have
packed things.

Even after examining an old Chinese typewriter, I doubt that there are
65,536 ideograms - and I doubt that there are more than 32,766
character sets

The question of how many characters there are is still the subject of
debate. In the 18th century, European scholars claimed the total tally
to be about 80,000. This number, however, is thought to be exaggerated
as the character count varies by dictionary and its comprehensiveness.
For example, the Kangxi Dictionary lists about 40,000 characters,
while the modern Zhonghua Zihai lists in excess of 80,000 (the most
comprehensive Japanese kanji dictionary Daikanwa Jiten lists 50,000
entries). One reason for the overwhelming number of characters is due
to the existence of rarely-occurring variant and obscure characters
(many of which are unused, even in Classical Chinese). Note, however,
that no two characters are ever contextually identical.

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