The data flow diagram for an online quiz app shows the flow of user interactions and system processes. Users authenticate, select quizzes, attempt questions, and submit their answers. The quiz management system fetches questions, evaluates answers, and stores results. It generates reports and updates the leaderboard. This DFD creates a clear and fun quiz. Users get quick feedback and results. A strong database and smooth data flow are key for a great quiz platform. They boost user engagement and improve learning results.