Public vs. Private – Which should I choose?
Choose Public if you are on a public computer, or a computer other than your own, so the computer you are using will NOT remember your username and password.
Choose Private if you are on your own private computer that you would prefer to have remember your username and password. You may be asked to receive a one-time “token” – a code that needs to be input the first time you use a private computer to authorize that computer for future access.
If you are in doubt as to which to select, always choose “Public” to be safe.