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QR Code

A two-dimensional barcode that stores data in a matrix pattern, readable by cameras and smartphones.

UtilitiesAlso called: "quick response code", "2d barcode"

QR codes bridge physical and digital worlds with camera-scannable data.

Capabilities

Store up to 4,296 alphanumeric characters.
Error correction (7-30% data recovery).
Fast scanning from any angle.
Support URLs, text, contact cards, WiFi credentials.

Security risks

QR phishing (quishing): Malicious codes lead to phishing sites.
No preview: Can't see destination before scanning.
Social engineering: Users trust QR codes too readily.
Payment fraud: Modified codes redirect payments.

Safe practices

Verify URL before visiting (most scanners show preview).
Avoid scanning codes in public places (stickers over legitimate codes).
Use scanner apps that preview URLs before opening.
Don't scan codes for sensitive actions (payments, login).

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