In inventory control, first in, first out [FIFO] means that stock is issued and charged out on the basis of the age of the inventory; the oldest stock is issued first. From an inventory control point of view this reduces the likelihood of stock write-offs, of obsolete or age-expired stock. From a costing point of view it reflects the actual price paid for the inventory. If stock is replenished at a different price, there is then a dilemma about pricing stock that has been bought at different prices. See also Last in, First Out.