Forecasting is the use of historic data to determine the direction of future trends. Forecasting is used by companies to determine how to allocate their budgets for an upcoming period of time.
Budgeting. A budget is a plan for your future income and expenditures that you can use as a guideline for spending and saving.
the key difference between a budget and a forecast is that the budget is a plan for where a business wants to go, while a forecast is the indication of where it is actually going.