Budgets are a measure of the results expected for the planned activities for a company. Whether you formally plan budgets or not, you will be working against several budgets – Revenue, Production, Expense, Financial, Investment and so on.
Once these budgets are recorded, you would periodically want to check up how your business measures up against this plan. And once you get a handle on the variance, you would probably take decisions on course corrections - record possible outcomes of these changes (as scenarios) and compare against the budgets once again.
This is a powerful planning mechanism that provides the flexibility to work in a changing /dynamic environment.
With Tally.ERP 9, you can set up any number of budgets - and to make this easy, budgets can roll up into 'group' budgets and these can roll up again into 'master' budgets: the people who come up with the budgets can make entries and the roll-up is automatic (and can be overridden at the rolled up level as well).
While viewing any report, you can choose to pull up the budgeted figures as well, along with a variance column. You could just as easily pull up budget figures alone - and make these available to various people.
A 'scenario' is the name given to a specific combination of vouchers that will be included to deliver a report - you can include and exclude different voucher types and build as many scenarios as needed – say one where a product launch is on time and another where it is delayed by three months. You could then view actual figures against a scenario. You could also see the variance between a scenario and the budget!
Budgets and Scenarios are powerful tools when used by themselves; used together they deliver unprecedented power to help plan & monitor your business.