If you've forgotten your password, you can reset it by following the steps below.
1. On the login page, click Forgot your password? — you'll receive an email with the subject "Password Reset Request"
2. Click the Set button in the email and set your new password.
3. Once you've set your new password, you can log in with it right away.
If you're asked for a password when paying for a ticket, see this article.