The U.S. Constitution is the supreme law of the land, and it lays out three branches of government: legislative, executive and judicial. The legislative branch makes laws; they're called Congresspeople. The executive branch implements those laws and enforces them through agencies like the FBI and the Department of Homeland Security; they're called Presidents. And the judicial branch interprets those laws, making sure they're being followed properly; they're called Judges. These three branches work together to keep our country running smoothly.