Let me start what VPN refers to: Virtual Private Network
A virtual private network (VPN) is a method of computer networking--typically using the public internet--that allows users to share information privately between remote locations, or between a remote location and a business' home network. A VPN can provide secure information transport by authenticating users, and encrypting data to prevent unauthorized persons from reading the information transmitted.The VPN can be used to send any kind of network traffic securely.
VPNs are frequently used by remote workers or companies with remote offices to share private data and network resources. VPNs may also allow users to bypass regional internet restrictions such as firewalls, and web filtering, by "tunneling" the network connection to a different region.
Technically, the VPN protocol encapsulates network data transfers using a secure cryptographic method between two or more networked devices which are not on the same private network, to keep the data private as it passes through the connecting nodes of a local or wide area network.