VPN stands for "Virtual Private Network" and describes the opportunity to establish a protected network connection when using public networks.
VPNs encrypt your internet traffic and disguise your online identity. This makes it more difficult for third parties to track your activities online and steal data.
A VPN works by encrypting your online presence.
The only way to decipher this encryption is with a key. Only your computer and the VPN know this key, making it impossible for your ISP to tell where you are browsing. Police can't track live, encrypted VPN traffic, but if they have a court order, they can go to your ISP (internet service provider) and request connection or usage logs. Since your ISP knows you're using a VPN, they can direct the police to them.