This document discusses inventory management. It defines inventory as items held to meet future demand, including raw materials, work in progress, finished goods, and supplies. Various inventory classification systems are described based on consumption, value, unit value, spare parts, availability, and source of supply. Different inventory costing methods are also outlined, including FIFO, LIFO, simple average, weighted average, and standard costing. An example is provided to calculate inventory value under LIFO, FIFO, and WAP methods.