What is a QR code and how does it work?

Related questions

1. How a QR code is generated?
2. Are QR codes free to use?
3. Can QR codes Be Hacked?
4. Is QR code safe?
5. Do QR codes work on Android?
6. How do QR codes store information?
7. Why QR code is better than barcode?
8. Are QR codes still used?
9. How is information stored in a QR code?
10. Where do QR codes come from?

Tags

1. #reader
2. #generated
3. #business
4. #means
5. #charge
6. #customer
7. #mostly
8. #anyone
9. #downloaded
10. #which
11. #smartphone