Cost accounting is the process of recording, classifying, and summarizing costs to determine the costs of products or services, plan and control costs, reduce costs, and provide information to management for decision making. The objectives of cost accounting include ascertaining costs, estimating costs, cost control, cost reduction, determining selling prices, and providing information for financial statements and operating policies. Costs are classified based on their nature as materials, labor, or expenses, and whether they are direct or indirect to a product, job, or process. Cost classification also considers variability, controllability, normality, and relevance to managerial decision making.