my $foo = 3;
my $bar = "keyword mania";
my @blivitz = "(some set of value);

##</code><code>##

my $bar = "keyword mania";
... (do something);
... (and something more);
bax($bar);                    # send $bar to sub bax for further processing
...(more code)

{                             # bare block
my @blivitz = ("7", '144', '1.16', "bat",);  # @blivitz values available only in this block
... do something with the elements of @blivitz;
}                             # end block

sub bax {                     # and here's the sub, bax
    my $foo = "3";
    ...do something to the value in $bar (a global) with $foo (available only in the sub);
    return (something);
}