Main Database : Type information to connect to the database.
DSN or File DSN : Data Source name in the ODBC settings.
Creating a File Source Name allows you to centralize and share them in order to be accessible from workstations. You won't have to create an ODBC for every workstation.
User : SYSADM.
Password : SYSADM.
Use Backup Database : Activate and set the backup database