Windows 8.x network category or network profile affects how other Windows machines detects or discover the node. A machine on a domain or private network will most of the time allow file sharing and printing, more relaxed firewall, etc.
For computers with multiple network interfaces changing network profile can be difficult using the GUI. To force a network interface to be in private profile for example you can do:
"Virtual Host-Only Network" - is the name associated with the network interface
"Private" - is the profile