Variables are useful for giving names to values referenced in a script, especially values that are referenced multiple times. For example,
CommandTerminator = "\r\n"
TFTPServerAddress = 192.168.10.50
TransferFileName= startup-config.txt
@login
@write "copy tftp start"
@write $(CommandTerminator)
@write "$(TFTPServerAddress)"
@write "(TransferFileName)"
@write $(CommandTerminator)