character class of Unicode 'marks', for example accent marks.
For the full list see L<perlunicode>.
-The Unicode has also been separated into blocks of charaters which you
-can test with C<\p{In...}> (in) and C<\P{In...}> (not in), for example
-C<\p{InLatin}, C<\p{InGreek}>, or C<\P{InKatakana}>. For the full list see
-L<perlunicode>.
-
-For the the full and latest information see the latest Unicode standard.
+The Unicode has also been separated into various sets of charaters
+which you can test with C<\p{In...}> (in) and C<\P{In...}> (not in),
+for example C<\p{InLatin}>, C<\p{InGreek}>, or C<\P{InKatakana}>.
+For the full list see L<perlunicode>.
C<\X> is an abbreviation for a character class sequence that includes
the Unicode 'combining character sequences'. A 'combining character
atop it, as in the word Angstrom. C<\X> is equivalent to C<\PM\pM*}>,
i.e., a non-mark followed by one or more marks.
+For the the full and latest information about Unicode see the latest
+Unicode standard, or the Unicode Consortium's website http://www.unicode.org/
+
As if all those classes weren't enough, Perl also defines POSIX style
character classes. These have the form C<[:name:]>, with C<name> the
name of the POSIX class. The POSIX classes are C<alpha>, C<alnum>,