which vpn tunnel style routes only certain types of traffic?
A VPN split tunnel routes only certain types of traffic, usually determined by destination IP address, through the VPN tunnel. All other traffic is passed through the normal internet connection.
A full VPN tunnel routes all of a user's network traffic through the VPN tunnel. This can sometimes send traffic that is not necessary.
A site-to-site VPN is a VPN implementation that uses routers on the edge of each site.
A host-to-host VPN implementation allows an individual host connected to the internet to establish a VPN connection to another host on the internet.