A VPN tunnel is a secure, encrypted connection between your device and a VPN server that protects your data as it travels across the internet. A VPN tunnel does two main things:

1. Turns your data into unreadable code (so it can’t be understood if intercepted)
2. Routes your traffic through a VPN server to hide your real IP address and activity

It’s called a “tunnel” because your data is isolated from the rest of the internet, traveling through a protected pathway instead of the open network. There are full tunnels, which have all traffic go through the VPN, and split tunnels, which only allow some traffic to go through.

Tunneling works through specific VPN protocols, or sets of rules that govern how the connection is built and how data moves through it. Common examples include OpenVPN, WireGuard, and IKEv2/IPSec. Different protocols offer different tradeoffs between speed and security, but they all accomplish the same basic job: building a secure channel for your data and encrypting what travels through it.