Definition
A Virtual Private Network is an encrypted tunnel between two endpoints — typically a user's device and a remote server — that lets traffic flow privately across an untrusted network like the public internet. The 'virtual' part means the network is constructed from existing physical infrastructure rather than requiring dedicated cables. The 'private' part means the contents are encrypted and the participants authenticated. Traffic that enters one end of the tunnel emerges at the other end indistinguishable from any other traffic originating there.
The Two Main Categories
Consumer VPNs are subscription services that route a user's traffic through provider-operated servers in many countries, providing privacy from ISPs and the ability to appear in different geographic locations. Enterprise VPNs (remote access and site-to-site) connect employees and offices to corporate networks. The protocols are the same — OpenVPN, WireGuard, IKEv2/IPSec — but the trust models, configuration, and goals differ substantially.
What a VPN Does and Does Not Do
A VPN encrypts traffic between your device and the VPN server, hides your real IP from the destination, lets you appear to be in another country, and blocks ISP and local-network observation of which sites you visit. It does not make you anonymous — the VPN provider sees your traffic, and accounts, cookies, and fingerprinting can still identify you. It does not protect against malware, phishing, or compromised endpoints. It does not encrypt traffic past the VPN server, where it returns to whatever protection (HTTPS or none) the destination provides.