Your login can be in 1 of 3 formats:
OWA Web Mail
This is the default option, select this if you wish to login to your email account and check your emails.
Select this if you wish to change things about your account. You can add or remove email addresses, set up a recovery email address and more.
This is a public or shared computer
Select this option if you use Outlook Web App on a public computer. Be sure to sign out when you've finished and close all windows to end your session.
This is a private computer
Select this option if you're the only person who uses this computer. Your server will allow a longer period of inactivity before signing you out.