What Is a VPN? How Virtual Private Networks Work and When You Need One

What Is a VPN?

A Virtual Private Network (VPN) is a service that creates an encrypted tunnel between your device and a VPN server, routing your internet traffic through that server before it reaches its destination. This does two things: encrypts your traffic so it can't be read by anyone between you and the VPN server, and replaces your real IP address with the VPN server's IP address, masking your location.

VPNs were originally developed for corporate use — allowing remote employees to securely access company networks over the public internet. Consumer VPNs have exploded in popularity for privacy and streaming purposes.

How VPNs Work Technically

1. Your device establishes an encrypted connection to the VPN server (using protocols like OpenVPN, WireGuard, or IKEv2)
2. Your internet traffic is encrypted before leaving your device
3. The encrypted traffic travels to the VPN server
4. The VPN server decrypts your traffic and forwards it to the destination website or service
5. The destination sees the VPN server's IP address, not yours
6. Responses travel back through the VPN server, are encrypted again, and sent to your device

What a VPN Protects You From

• Your ISP monitoring your traffic: Your internet service provider can see every website you visit. A VPN encrypts this, preventing ISP surveillance and data selling (ISPs can sell browsing data to advertisers in the U.S.).
• Network-level eavesdropping: On public Wi-Fi (coffee shops, airports, hotels), other users on the same network could potentially intercept unencrypted traffic. A VPN prevents this.
• IP-based location restrictions: Websites can be blocked or show different content based on your IP address (geo-restrictions). A VPN server in another country bypasses this — enabling access to streaming libraries available in other regions.
• Basic tracking by IP address: Advertisers and websites tracking your IP address won't see your real IP.

What a VPN Does NOT Protect You From

• Website tracking via cookies and fingerprinting: Once you log into a website, it knows who you are regardless of your IP. Browser fingerprinting can identify you without cookies.
• Malware: A VPN is not an antivirus. It doesn't prevent malware infections.
• The VPN provider itself: By using a VPN, you're shifting trust from your ISP to your VPN provider. If the VPN provider logs your activity or is compelled by law enforcement to provide records, your privacy is not protected. This is why choosing a trustworthy, audited no-logs VPN matters.
• DNS leaks, WebRTC leaks: Poorly configured VPNs can leak your real IP address through these channels.

Choosing a VPN

Key factors:

• No-logs policy (independently audited): Provider should not keep records of your activity, confirmed by third-party audit
• Jurisdiction: Providers in privacy-friendly jurisdictions (Panama, British Virgin Islands) are less subject to compelled disclosure. U.S., UK, and EU-based providers face data retention laws and law enforcement requests.
• Protocol: WireGuard is the modern standard — fast and well-audited. OpenVPN is established and open-source.
• Speed: Good VPNs add minimal latency; poor ones can significantly slow connections
• Avoid free VPNs: Free VPN services typically monetize by logging and selling your data — the opposite of privacy protection. Pay for a reputable service.

Reputable paid options (as of 2025): Mullvad, ProtonVPN, NordVPN, ExpressVPN. No VPN is perfect, but reputable paid providers are far better than free alternatives.