The Postal Service Analogy
To understand privacy, you need to understand how the internet moves data. Imagine sending a letter.
- IP Address: Your house address. Every website needs this to know where to send the data back to.
- Data Packets: The envelopes containing the information.
- Router: The local post office that sorts the mail.
Key Concepts
1. IP Addresses
Every device has a public IP address (like 124.55.21.9).
- The Privacy Risk: Websites use your IP to track your approximate location (City/State) and identify you.
- The Fix: A VPN hides your IP address, replacing it with the VPN server's address.
2. DNS (Domain Name System)
Computers don't speak English; they speak numbers. When you type google.com, your computer needs to find the IP address (142.250.190.46). It asks a "DNS Resolver" to look this up.
- The Privacy Risk: By default, your Internet Service Provider (ISP) runs your DNS. This means they see a list of every single website you visit, even if the content is encrypted.
- The Fix: Use a private DNS provider like Cloudflare (1.1.1.1) or Quad9. Cloudflare audits its systems to prove they don't sell your browsing history.
3. HTTPS vs HTTP
- HTTP: Sending a postcard. Anyone who handles the mail (ISP, Hacker, Government) can read the message written on the back.
- HTTPS: Sending a locked box. Only the sender and the receiver have the key to open it.
- Status: Today, 98%+ of web traffic is HTTPS.
- Limit: The "address" on the box (the domain name) is still visible. They know where you sent the box, just not what is inside.
Advanced Tracking: Beyond the IP
Hiding your IP isn't enough anymore. Advertisers use Browser Fingerprinting.
They look at tiny details of your browser:
- Your screen resolution (e.g., 1920x1080).
- Your installed fonts.
- Your battery level.
- Your browser version.
When combined, these details create a unique "fingerprint" that is specific to you. You can test how unique your browser is at the EFF's Cover Your Tracks.
The Defense: This is why we recommend Firefox. It has built-in "Fingerprinting Protection" that lies to websites, making your computer look generic and boring, so you blend in with the crowd.
