Grades are a system used to evaluate a student's performance in school. They typically range from letters, such as A, B, C, D, and F, with A being the highest and F indicating failure. Grades are often based on tests, assignments, and participation, reflecting how well a student understands the material. Teachers use grades to provide feedback and help students identify areas for improvement. In many educational systems, grades can influence a student's future opportunities, such as college admissions or scholarships. Overall, grades serve as a standardized way to measure academic achievement.