Tournament structures refer to the organized formats used to conduct competitive events, where participants compete for a title or prize. Common structures include single elimination, where a participant is out after one loss, and double elimination, which allows a participant to lose once before being eliminated. Round-robin is another format, where each participant competes against every other participant, ensuring a comprehensive assessment of skills. These structures help in managing the flow of the tournament and determining the winner efficiently. They can be applied to various sports and games, including basketball, tennis, and esports, making them versatile for different competitive scenarios.