In Variables§

See primary documentation in context for The our declarator

our variables are created in the scope of the surrounding package. They also create an alias in the lexical scope, therefore they can be used like my variables as well.

module M {
    our $Var;
    # $Var available here
}

# Available as $M::Var here.

In order to create more than one variable with package scope, at the same time, surround the variables with parentheses:

our ( $foo, $bar );

see also the section on declaring a list of variables with lexical or package scope.