You look at shoes once, then see shoe ads everywhere. Here’s how it works.
Cookies:
Ad companies drop tracking files on millions of websites. When you visit Site A then Site B, they see both visits and build a profile.
It gets worse:
- Fingerprinting — Identifies you by browser details even without cookies
- Cross-device tracking — Connects your phone, laptop, and tablet
- Data brokers — Buy and sell your information
How to stop it:
- Use a browser that blocks trackers
- Install an ad blocker
- Reject non-essential cookies
See: Privacy browsers