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Why character set translation tables are needed
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   DOS uses a different character code mapping than Unix. 7-bit
characters still have the same meaning, only characters with the eight
bit set are affected. To make matters worse, there are several
translation tables available depending on the country where you are.
The appearance of the characters is defined using code pages. These
code pages aren't the same for all countries. For instance, some code
pages don't contain upper case accented characters. On the other hand,
some code pages contain characters which don't exist in Unix, such as
certain line-drawing characters or accented consonants used by some
Eastern European countries. This affects two things, relating to
filenames:

upper case characters
     In short names, only upper case characters are allowed. This also
     holds for accented characters. For instance, in a code page which
     doesn't contain accented uppercase characters, the accented
     lowercase characters get transformed into their unaccented
     counterparts.

long file names
     Micro$oft has finally come to their senses and uses a more standard
     mapping for the long file names. They use Unicode, which is
     basically a 32 bit version of ASCII. Its first 256 characters are
     identical to Unix ASCII. Thus, the code page also affects the
     correspondence between the codes used in long names and those used
     in short names

   Mtools considers the filenames entered on the command line as having
the Unix mapping, and translates the characters to get short names.  By
default, code page 850 is used with the Swiss uppercase/lowercase
mapping. I chose this code page, because its set of existing characters
most closely matches Unix's. Moreover, this code page covers most
characters in use in the USA, Australia and Western Europe. However, it
is still possible to chose a different mapping. There are two methods:
the `country' variable and explicit tables.