The Usage of rc.conf file

Under the directory /etc, the rc.conf file is definitely regarded as the system configuration file. During the first attempting installation of FreeBSD, the utilization of rc.conf is of following:

1. To run the Gnome Display Manager (GDM) in order to start up the GNOME environment as long as the system start up. Adding gdm_enable="YES"
   
2. To Customize the DHCP of the network. Adding ifconfig_em0="DHCP"