THE WAR ON WAGES:

Amazon's fulfillment center, located in the township of Robbinsville, is a dizzying hive of activity, with humans and machines working in carefully coördinated harmony. Besides showing the incredible efficiencies of Amazon's operations, the factory hints at how, over the coming decades, technology may start to assist human workers with many simple manual tasks. How far this change goes, and how quickly it comes about, could make a significant difference to the labor market (see "Who Will Own the Robots?").

At the center of the warehouse is a storage space containing square shelves packed with countless products from Amazon's inventory. In previous generations of its fulfillment center, Amazon's workers would have roamed these shelves searching for the products needed to fulfill each new order. Now the shelves themselves glide quickly across the floor carried atop robots about the size and shape of footstools. In a carefully choreographed dance, these robots either rearrange the shelves in neatly packed rows, or bring them over to human workers, who stack them with new products or retrieve goods for packaging.

Amazon's robotic shelves allow more products to be packed into a tighter space. They also make stacking and picking more efficient by automatically bringing empty shelves over to packers or the right products over to pickers. The process is more efficient than having humans walk around, so it also a good example of how automation can be combined with human labor to increase productivity.

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