Public opinion is measured through methods such as polling, surveys, and focus groups. These tools gather data on citizens' views, preferences, and attitudes regarding various political issues and leaders. Understanding public opinion is important for policymakers, as it informs decision-making, guides political campaigns, and shapes policies. By gauging the electorate's sentiments, politicians can tailor their messages and actions to align with constituents' interests, fostering a responsive and accountable governance that reflects the will of the people.