1) If I declare a variable $first in a FirstFile.pl at the top without "my" , does it become package variable ? What package does it belong to ? How can it be accessed in SecondFile.pl ?
2) If a variable is declared as "$first" and another variable is declared as "my $second" in FirstFile.pl at the beginning of the program, can "my $second" variable be used in subroutines of FirstFile.pl ? I guess "$first" can be used in subroutines of the FirstFile.pl
3) $first is declared as package variable. But what package does it belong to ? How this variable be accessed in SecondFile.pl ? I guess "my $second" can not be used in SecondFile.pl