Un-limited Questions - With an account you will be able to practice all the questions without any restriction.
Save a Test - You need an account to "Save a Test" if you could not finish practising all the questions at one go, so that
you can resume the practice next time when you logged in.
Store Missed/Flagged Questions - Your missed or flagged questions will be automatically stored for later review if you have an account,
otherwise they will be discarded after your current practice session.