Rating systems are tools used to evaluate and compare products, services, or experiences based on specific criteria. They often use a numerical scale, such as 1 to 5 stars, or letter grades, like A to F, to convey quality or satisfaction. These systems help consumers make informed decisions by summarizing feedback from multiple users or experts. Common examples of rating systems include those used by movie review websites, restaurant guides, and product review platforms. They can also be found in educational assessments and employee performance reviews. Overall, rating systems provide a standardized way to assess and communicate value.