This is possible because virtualization makes cloning software very easy, and Networked Attached Storage devices have extremely sophisticated ways of making virtual copies of large amounts of data and then tracking the changes between the two copies, which saves massive amounts of storage.

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This is good until the dealer shuffles and then you start tracking the cards again.

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For if we do go back to a system of not tracking then such advertising companies become simply wholesalers of an undifferentiated good.

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