The document that serves as the foundation of modern U.S. law is the United States Constitution. Drafted in 1787 and ratified in 1788, it established the framework for the federal government, outlining the separation of powers among the legislative, executive, and judicial branches. The Constitution also includes fundamental principles such as checks and balances and the Bill of Rights, which protects individual freedoms. As a living document, it has been amended to address societal changes and challenges over time, continuing to influence American law and governance. The Constitution is often regarded as a symbol of democracy and the rule of law.