A questionnaire is a list of questions typically given to participants at an event, or to consumers of a product, in order to receive feedback or information on the subject. According to About.com, a questionnaire is typically printed.
Questionnaires provide a standardized form of feedback, which allows bodies to accumulate information. This information is often used to alter current practices, assess public consensus or generate statistical data, among other things. For example, a professor may ask his students to complete a questionnaire at the end of term in order to determine the positive and negative perceptions of his students. Another use of a questionnaire is in marketing, where a company asks participants to rate its product on a variety of scales.