This document discusses inventory costing and cost of goods sold. It provides examples of how to calculate inventory and cost of goods sold using different costing methods like FIFO, LIFO, and weighted average. FIFO assigns the oldest costs to cost of goods sold and most recent costs to ending inventory. LIFO does the opposite by assigning most recent costs to cost of goods sold. Weighted average assigns an average unit cost. The choice of method affects reported income and taxes. Inventory is also reported at the lower of cost or market value. Managers may choose methods to maximize reported income and minimize taxes within GAAP.