A budget is a financial plan for a defined period, usually a year, that includes planned sales, resources, costs, expenses, assets, liabilities and cash flows. Budgeting tools provide a forecast of revenues and expenditures to construct a model of potential financial performance. There are several types of budgets including sales, production, capital, revenue, expenditure, cash flow, and zero-based budgets. Cost control is the process of maintaining costs according to established norms and focuses on decreasing total costs through corrective actions when actual costs vary from standards. It involves controlling costs for materials, labor including direct and indirect labor, and overhead costs.