Virtual Private Network.
Its basically a normal network such as an office network that can be accesed over a public network or your home network via a secure point to point connection.
You can pay for a vpn service to makesure that all of your internet traffic is encrypted to keep the bad guys out.
I pay for "Private Internet Access". I tested it out and it really works well. I was able to get one of my friends passwords (with his permission) using wire shark while he was using unencrypted internet, but after he turned on private internet access vpn I couldnt see his passwords or any of the sites he was visiting.