There are two ways that your module could be using another module.

1. It directly uses that modules functionality, like Carp or CGI or Exporter. This could either be through function calls or an @ISA relationship.
2. It is passed an object of a given class.

In the first case, where a user of your module would expect that this given functionality be there automatically, then I would put a use in your module and document that your module depends on other modules being installed.

In the second case, I would not do a use on that module, because you're not actually instantiating that object, but are being given the object. The use has to have already been done for the object to be given to you.

Your initial questions on POD can be answered at perlpod and by reading a number of the submissions in the Code Catacombs.

I'd also like to commend you for actually taking the time to consider these issues. ++!

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