What Is a VPN?

Learn how VPNs work, what they protect, and when you should use one.

What Is a VPN?

A VPN (Virtual Private Network) creates an encrypted tunnel between your device and a VPN server. All your internet traffic flows through this tunnel, hiding your activity from your ISP, network administrators, and potential eavesdroppers.

How a VPN Works

Without a VPN:

Your Device → ISP → Website
(ISP sees everything)

With a VPN:

Your Device → [Encrypted Tunnel] → VPN Server → Website
(ISP sees encrypted data only)

When you connect to a VPN:

  1. Your device establishes an encrypted connection to the VPN server
  2. All your internet traffic is routed through this tunnel
  3. The VPN server makes requests on your behalf
  4. Websites see the VPN server's IP instead of yours

What a VPN Protects

  • Privacy from ISP — Your ISP can't see which websites you visit
  • Public Wi-Fi security — Encrypts your data on untrusted networks (cafes, airports)
  • IP masking — Websites see the VPN server's IP, not yours
  • Bypass censorship — Access content restricted by network administrators or governments

What a VPN Doesn't Protect

  • Browser fingerprinting — Websites can still identify you through browser characteristics
  • Logged-in accounts — Google still knows it's you if you're logged in
  • Malware — A VPN doesn't replace antivirus software
  • Complete anonymity — The VPN provider can see your traffic (choose a no-logs provider)

When to Use a VPN

Situation VPN Recommended?
Public Wi-Fi (cafe, airport) Yes — protects against eavesdropping
Working remotely Yes — secures connection to company resources
Sensitive browsing Yes — adds a layer of privacy
General home browsing Optional — your home network is usually trusted
Online gaming Rarely — adds latency

Choosing a VPN

Look for these features when selecting a VPN provider:

  • No-logs policy — The provider doesn't store your browsing history
  • Strong encryption — AES-256 or ChaCha20
  • Kill switch — Blocks internet if the VPN connection drops
  • DNS leak protection — Prevents DNS queries from bypassing the tunnel
  • WireGuard support — Modern, fast protocol

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