In a one-file script, there is no difference between my, our, and use vars, when declaring a variable outside any given block.

However, the difference comes in when working with functions or multi-file applications.

• my says that this variable cannot be used outside its scope. When this scope goes away, this variable is killed.
• our says that this variable cannot be used outside its scope. When this scope goes away, this variable stays around.
• use vars says that this variable gets to ignore strict. It has no scope (other than the whole program).

A good code example would be the following:

sub foo {
    my $x;
    $x++;
    return $x;
}

print foo() for (0 .. 10);
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Try that, then change my to our. You'll see what I mean.

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/me wants to be the brightest bulb in the chandelier!

Vote paco for President!