A referendum is a direct vote in which an entire electorate is invited to approve or reject a particular proposal, often related to constitutional amendments, changes in law, or key decisions affecting policy. It serves as a tool for direct democracy, allowing citizens to have a say in significant governmental issues. Referendums can differ in their implementation and significance, depending on the country and context. The results can shape public policy and reflect the will of the people, often necessitating government action based on the outcome of the vote.