$str = "aa bb cc";

# scalar context
$a = $str =~ m/(\w+)/;
print "$a\n";
# prints 1

# list context (1 element list $a)
($a) = $str =~ m/(\w+)/g;
print "$a\n";
# prints aa

# list context (multi element array list)
@a = $str =~ m/(\w+)/g;
print "@a\n";
# prints aa bb cc