Methods to track and monitor inventory go back as far as writing itself. The Sumerians, Babylonians and Egyptians after them, marked their grain containers to indicate both content and amount. Modern techniques for scientific materials management, however, are a far more recent development. Beginning with the expansion of railroads in the United States, and the heavy industry that accompanied that growth, businesses increasingly began to be conscious of how and when they ordered supplies and shipped finished goods. Frederick Winslow Taylor’s principles of scientific management encouraged the economical use of materials to help to reduce the cost of production in the early twentieth century, although Charles Babbage had already laid the foundation for materials management earlier in the nineteenth century. Detailed and intensive control of supplies became a more widespread concern with the US entry into World War I, and gradually grew thereafter.
Even after the First World War, most businesses employed a “push” model for materials management. The experience of nineteenth-century heavy industry had caused manufacturers to order an abundance of stock, which they maintained in voluminous warehouses, to ensure constant production and prevent costly interruptions in the manufacturing process. This method meant that producers often found themselves with large supplies of raw materials or finished products that needlessly occupied space until demand was strong enough to deplete their excess supplies. After World War II, however, businesses moved toward a “pull” method of inventory control that focused on ordering additional materials only when supplies fell to a pre-determined level. While the “pull” model allows for more efficient use of space, it requires better forecasting to determine what level is the appropriate point at which to place an order and to account for delays in communication or slow lead time. The demand for better forecasts improved overall materials management and required closer attention to consumer demand, operations and inventory measurement.