While not totally accurate, a convenient way of thinking of our is as a lexically-scoped "no strict;" for specific variables.

our is lexically scoped, so its effect will end at the end of Mylib.pm. From that point on, you'll have to refer to $Mylib::$variable1 as $Mylib::$variable1 unless you use some other method of aliasing $variable1 to $Mylib::$variable1.

print("\$variable1 = $Mylib::variable1\n");  # OK
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use Mylib qw( $variable1 );           # If Mylib exports $variable1
print("\$variable1 = $variable1\n");  # OK
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our $variable1;
local *variable1 = \$Mylib::variable1;  # Create an alias.
print("\$variable1 = $variable1\n");    # OK
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use Data::Alias qw( alias );
alias my $variable1 = $Mylib::variable1;  # Create an alias.
print("\$variable1 = $variable1\n");      # OK
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