Write a short note on questionnaire.

A questionnaire is a research instrument consisting of a set of questions designed to gather data from respondents for the purpose of research or survey. It can be structured or unstructured, depending on the nature of the study. Questionnaires are commonly used in quantitative research to collect standardized data from a large number of participants efficiently. They can cover a wide range of topics and are often administered through various methods such as in-person interviews, mail surveys, online surveys, or telephone interviews. Questionnaires offer researchers a systematic way to collect information, allowing for easy comparison and analysis of responses. However, careful design and piloting are essential to ensure clarity, relevance, and validity of the questions, as well as to minimize response bias.