It charts the government's expenditures and allocates its resources for a period of one fiscal year. But budgets always relate to fiscal years because of their dependence on tax revenues. Modern government budgets make a clear separation between current expenditures and the development elements. These were mixed in the past and this served to cloud issues and to disguise gross misuse of funds. But this structural separation did not change anything basic.
Budgets are statements, mainly of policy.
In this sense, a budget is also a monitoring tool. A budget is a promise, it is a contract between the elected government and the nation, it is approved by parliament and has the status of a law. A budget can be altered only through a vote in parliament. It is a document of unparalleled importance, second only to the constitution. As circumstances change, new priorities and emergencies alter the allocation of resources.