Display User Name
Toggle this checkbox on to display the User Name of the individual that is currently logged in. The default is for this checkbox to be left blank. This information will be displayed within parentheses ( ) after the user's Display Name. This web part is not active if the user is an anonymous user.
Display ‘Currently Logged In As’
Toggle this checkbox on to display "Currently Logged In As" above the user's Display Name and/or Display Name (User Name), separated by a horizontal line above and below. This property is selected by default.
Override Display
Any text entered in this field box will be displayed instead of the “Currently Logged In As” information.