Public finance is a branch of economics that deals with the revenue and expenditure of governments at various levels, including local, state, and federal. It involves the study of how governments can raise funds through taxation, borrowing, and other means, and how these funds are allocated and spent on public goods and services such as education, healthcare, infrastructure, and defense. Public finance also examines the impact of government policies on economic growth, income distribution, and public welfare. Overall, the goal of public finance is to ensure the efficient and equitable use of public resources to achieve societal goals and promote economic development.