Definitions
Periodic inventory review involves counting and documenting inventory at specified times. For example, a retail store operating under a periodic review policy might count inventory at the end of each month. Continuous inventory review, also known as perpetual review, involves a system that tracks each item and updates inventory counts each time an item is removed from inventory. For example, a retailer may use bar code scanners to record customer purchases and update inventory counts every time a cashier scans a product code.