We do not collect any personal data about our users. Traffic to the server is saved in automatic server traffic logs, which consist of IP adresses, date and time, request lines etc. Check out the Wikipedia article on Common Log Format to see more about how this works.

As the service grows, we will probably allow users to save preferences, progress and other things to their accounts, and this will have to be saved in our database, but we will never require any personal information (other than a login) in order to use the service, or collect such information without users' consent.