Questionnaires created with the purpose of extracting information and deriving conclusions from a set of users. Use this tag for questions related to the creation, storage and handling of surveys. Note: Asking people to take a survey is off-topic.
Surveys generally aren't given too much attention by those who are uninterested in a certain topic, or are given unsolicited requests to answer them. Often times they are prone to intentional negligence by answerers, which can very easily skew results and should be carefully filtered out to prevent this. Nonetheless, surveys can provide powerful insights into a specific area of knowledge if implemented correctly.
Perhaps a website is interested to see if a specific set of users are satisfied with the website, namely those users with IP addresses which have only ordered their first few items. This would be very important to ensure that they can retain new customers and improve any shortcomings. They might also want to ask for suggestions from users who have used their website for an extended period of time, longer than 1 year. Creating surveys with these metrics allows for targeted information extraction, and thus the ability to draw specific conclusions from this data.
Surveys may be implemented in software using a variety of programming languages. Popup windows, modules, and follow-up emails are all viable options.