A questionnaire is a research tool consisting of a series of questions designed to gather information from respondents. It can be used in various fields, such as psychology, market research, and sociology, to collect data on opinions, behaviors, or demographics. Questionnaires can be administered in different formats, including paper, online, or face-to-face, making them versatile for different research needs. Typically, questionnaires include closed-ended questions, which provide specific response options, and open-ended questions, allowing for more detailed answers. The design of a questionnaire is crucial, as clear and concise questions lead to more accurate and reliable data. Properly analyzed, the information gathered can help inform decisions and understand trends within a population.