A virtual private network (VPN) extends a private network across a public network. It enables users to send and receive data across shared or public networks as if their computing devices were directly connected to the private network. As a result, applications running across a VPN may benefit from the private network's functionality, security, and management.

Computer Network Terms II

A computer network is a set of computers sharing resources located on or provided by network nodes. The computers use common communication protocols over digital interconnections to communicate with each other. The connections between nodes are established using either physically wired, optical, or wireless radio-frequency that may be arranged in various network topologies. The best-known computer network is the Internet.