This document provides an overview of public budgets. It begins by defining what a budget is, including that it is a formal estimate of required resources for a given time period. It then discusses different definitions of budgets provided by various scholars. The document outlines the key components of a budget as public expenditures and public revenues. It also discusses different types of budgets, including operating and development budgets. The document further examines classifications of public expenditures by categories, sectors, general objects, and programs/activities. Finally, it introduces the concept of the canon of public expenditures as rules or principles that governments must follow when incurring expenditures.