Correct a few typos and reformulate some sentences here and there.

lib/Data/Util.pm

@@ -142,8 +142,10 @@ This document describes Data::Util version 0.63
 This module provides utility functions for data and data types,
 including functions for subroutines and symbol table hashes (stashes).
 
-The implementation of this module is both Pure Perl and XS, so if you have a C
-compiler, all the functions this module provides are really faster.
+This module makes for a pure Perl and XS implementation. 
+
+However, if you want to use the full capacity of it, we recommend you to opt
+for the XS backend.
 
 There are many benchmarks in the F<DIST-DIR/benchmark/> directory.
 
@@ -154,44 +156,44 @@ There are many benchmarks in the F<DIST-DIR/benchmark/> directory.
 Check functions are introduced by the C<:check> import tag, which check
 the argument type and return a bool.
 
-These functions also checks overloading magic, e.g. C<${}> for a SCALAR reference.
+These functions also check for overloading magic, e.g. C<${}> corresponds to a SCALAR reference.
 
 =over 4
 
 =item is_scalar_ref(value)
 
-For a SCALAR reference.
+Checks for a SCALAR reference.
 
 =item is_array_ref(value)
 
-For an ARRAY reference.
+Checks for an ARRAY reference.
 
 =item is_hash_ref(value)
 
-For a HASH reference.
+Checks for a HASH reference.
 
 =item is_code_ref(value)
 
-For a CODE reference.
+Checks for a CODE reference.
 
 =item is_glob_ref(value)
 
-For a GLOB reference.
+Checks for a GLOB reference.
 
 =item is_rx(value)
 
-For a regular expression reference generated by the C<qr//> operator.
+Checks for a regular expression reference generated by the C<qr//> operator.
 
 =item is_instance(value, class)
 
-For an instance of I<class>.
+Checks for an instance of I<class>.
 
-It is equivalent to something like
+It is equivalent to the following statement:
 C<< Scalar::Util::blessed($value) && $value->isa($class) >>.
 
 =item is_invocant(value)
 
-For an invocant, i.e. a blessed reference or existent package name.
+Checks for an invocant, i.e. a blessed reference or existent package name.
 
 If I<value> is a valid class name but does not exist, it will return false.
 
@@ -235,8 +237,8 @@ This function has no counterpart for validation.
 
 =head2 Validating functions
 
-Validating functions are introduced by the C<:validate> tag which check the
-argument and returns the first argument.
+Validating functions are introduced by the C<:validate> tag which checks for
+the argument and returns the first argument.
 These are like the C<:check> functions but dies if the argument type
 is invalid.
 
@@ -246,49 +248,49 @@ These functions also checks overloading magic, e.g. C<${}> for a SCALAR referenc
 
 =item scalar_ref(value)
 
-For a SCALAR reference.
+Validates a SCALAR reference.
 
 =item array_ref(value)
 
-For an ARRAY reference.
+Validates an ARRAY reference.
 
 =item hash_ref(value)
 
-For a HASH reference.
+Validates a HASH reference.
 
 =item code_ref(value)
 
-For a CODE reference.
+Validates a CODE reference.
 
 =item glob_ref(value)
 
-For a GLOB reference.
+Validates a GLOB reference.
 
 =item rx(value)
 
-For a regular expression reference.
+Validates a regular expression reference.
 
 =item instance(value, class)
 
-For an instance of I<class>.
+Validates an instance of I<class>.
 
 =item invocant(value)
 
-For an invocant, i.e. a blessed reference or existent package name.
+Validates an invocant, i.e. a blessed reference or existent package name.
 
 If I<value> is a valid class name and the class exists, then it returns
-the canonical class name, which is logically cleaned up. That is, it does
-C<< $value =~ s/^::(?:main::)*//; >> before returns it.
+the canonical class name, which is logically cleaned up. That is, it runs
+C<< $value =~ s/^::(?:main::)*//; >> before returning it.
 
 NOTE:
-The canonization is because some versions of perl has an inconsistency
-on package names:
+Canonization is done so due to an inconsistency between Perl versions. 
+For instance:
 
 	package ::Foo; # OK
 	my $x = bless {}, '::Foo'; # OK
 	ref($x)->isa('Foo'); # Fatal
 
-The last sentence causes a fatal error:
+The last code snippet causes a fatal error:
 C<Can't call method "isa" without package or object reference>.
 However, C<< invocant(ref $x)->isa('Foo') >> is always OK.
 
@@ -460,14 +462,16 @@ For example:
 
 =head2 DATA_UTIL_PUREPERL
 
-If true, C<Data::Util> uses the Pure Perl implementation.
+If true, C<Data::Util> uses the pure Perl implementation.
 
 =head1 DEPENDENCIES
 
 Perl 5.8.1 or later.
 
-If you have a C compiler, you can use the XS backend,
-but the Pure Perl backend is also available if you have no C compilers.
+If you have a C compiler, you can use the XS backend.
+
+A pure Perl backend/implementation is also made available in case you have no C
+compiler handy (unlikely!).
 
 =head1 BUGS AND LIMITATIONS