What is a QR Code and How Does it Work?

Introduction

QR codes (Quick Response codes) are two-dimensional barcodes that can store various types of information. Originally invented in 1994 by Denso Wave for tracking automotive parts, QR codes have become ubiquitous in our daily lives.

How QR Codes Work

QR codes work by encoding data in a pattern of black and white squares. When you scan a QR code with your smartphone camera, the device's software decodes this pattern and extracts the embedded information.

Key Components

**Finder Patterns**: The three large squares in the corners help scanners locate and orient the code.

**Alignment Pattern**: Helps correct distortion when scanning at angles.

**Timing Pattern**: Alternating black and white modules that help determine the size of the data matrix.

**Data Area**: The main body where the actual information is encoded.

Types of Information QR Codes Can Store

URLs and website links

Contact information (vCards)

WiFi network credentials

Plain text messages

Email addresses

Phone numbers

Geographic locations

And much more!

Error Correction

One of the brilliant features of QR codes is their error correction capability. Even if part of the code is damaged or obscured, it can still be read. There are four levels of error correction:

**L (Low)**: ~7% recovery

**M (Medium)**: ~15% recovery

**Q (Quartile)**: ~25% recovery

**H (High)**: ~30% recovery

Conclusion

QR codes have revolutionized how we share and access information. Their versatility, reliability, and ease of use make them an essential tool for businesses and individuals alike.