This website is powered with Drupal which is a very popular and powerful open-source content management system (CMS). Webform is a Drupal module (or plugin) and it is a user-friendly and powerful online survey tool.
"Webform is the module for making forms and surveys in Drupal. After a submission customizable e-mails can be sent to administrators and/or submitters. Results can be exported into Excel or other spreadsheet applications. Webform also provides some basic statistical review and has an extensive API for expanding its features."