This is a very basic description of what VPNs are all about

Virtual Private Network is a computer network in which some of the links between nodes are carried by open connections or virtual circuits in some larger networks, such as the internet, as opposed to running across a single private network.  The link layer protocols of thevirtual network are said to be tunneled through the transport network. [2]  In mid 1990s, the rise of the Internet and the increase of speed for cheap Internet connections paved the way for new technologies. Many developers, administrators, and, last but not the least, managers had discovered that there might be better solutions than spending several hundreds of dollars, if not thousands of dollars, on dedicated and dial-up access lines.  The idea was to use the Internet for communication between branches and at the same time ensure safety and secrecy of the data transferred. In other words: providing secure connections between enterprise branches via low-cost lines using the Internet. This is a very basic description of what VPNs are all about.  Taking into account literally the acronym VPN (Virtual Private Network) Virtual means there is no direct network connection between the two communication partners, but only a virtual connection provided by VPN. Software, realized normally over public internet connection. And considered to be private because only the members of the company connection by the VPN software are allowed to read data transform.[3] With a VPN The network entities are described as a set of logical connections secured by special software that establishes privacy of safeguard the connection endpoint. As depicted in the Today the Internet is a work medium used, and privacy is achieved by modern cryptographic methods.