One of the major competitive strategies which engineered and sustains this colossal network of stores is the just-in-time inventory management system.

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It looks like Napster is going to be the first to take the plunge and use Microsoft's new digital rights management system (codenamed Janus) that lets online music stores rent, rather than sell, downloads to people.

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The inventory management system enables both Walmex and its suppliers to figure out which goods sold how much in which stores on the previous day.

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