Upon registration, the password field is required, and will determine the password that you will use to log into the system from now on.
When updating your profile this field is for resetting your password to a different password. If left untouched, your present password will be preserved. If it is changed in both the password text box and the confirm text box, your password will be updated in the system.
Please note: if you have not verified your e-mail address, you will not receive e-mail notifications, even if this box is checked.