This document discusses inventory control and recent trends in production planning and control (PPC). It defines inventory and describes different types of inventory classified by material flow and nature of use. It also discusses the purpose of holding stock, inventory control including economic order quantity, inventory costs, and terms used. The document then covers recent trends in PPC like applications of computers, computerized PPC systems, Just-in-Time production, Kanban system, Manufacturing Resource Planning (MRP II), Enterprise Resource Planning (ERP) and its implementation and modules.