Warehouse Management System is your WMS, a software application, it is the inventory control system that manages your warehouse, what goods are coming in, provides the capability to receive goods, putaway them, then you can fulfill orders against the inventory you have received by downloading orders into the WMS and then ship goods against the orders.
I am not sure what is the Warehousing Management System - The other system that uses the warehouse term is the Data Warehouse System, which is also a software application but to manage your data - Are you referring to this system?
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