Process costing, which will he discussed in Chapter 6,is used when all units worked on within a department or other work area are homogeneneous,or there is no need to distinguish among units, or when it is not practical to do so. Process costing accumulates all the cost of operating a process for a period of time and then divides the costs by the number of units of product that passed through that process during the period; the result is unit cost. If the product of one process becomes the material of the next, a unit cost is computer for each process.