LAN: Generic Local Network. Uses pfSense for DNS queries. SPAM filtering on.
CLEAR: Completely clear network. No SPAM filtering at all, etc. Uses external DNS. Acts also as a backup to the internet just in case the filtering on the LAN network somehow prevents access to the internet.
IOT: For untrusted IOT devices. No access to other networks. Forces internal DNS and NTP to be used. SPAM filtering on.
GUEST: For Guests. No access to other networks. Allows external DNS to be used by guests. SPAM filtering on.