As an example of package-global versus lexical naming rules and also the scoping effects touched on elsewhere in this thread, consider:

Win8 Strawberry 5.8.9.5 (32)  Wed 04/28/2021 19:35:55
C:\@Work\Perl\monks
>perl -l

use strict;
use warnings;

our $foo = 'package global';

{  # begin scope

my $foo = 'lexical';

print 'A: ', $foo;
print 'B: ', $::foo;
print 'C: ', $main::foo;

}  # end scope

^Z
A: lexical
B: package global
C: package global
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Now try the code without the { ... } scope. Is there any difference? If so, why? Is there any way to do without the our declaration in the
    our $foo = 'package global';
assignment statement? Is there any reason to avoid our? See also perldata.