What is QR Code?
QR Code (Quick Response Code) is a two-dimensional matrix barcode that can store various types of data including URLs, text, contact information, and more. It was invented in 1994 by Denso Wave for tracking automotive parts and has since become ubiquitous for mobile scanning applications.
Quick Facts
| Full Name | Quick Response Code |
|---|---|
| Created | 1994 by Denso Wave (Masahiro Hara) |
| Specification | Official Specification |
How QR Code Works
QR codes consist of black squares arranged on a white background in a square grid pattern. They include three distinctive square patterns in the corners for alignment and can store up to 7,089 numeric characters or 4,296 alphanumeric characters. QR codes feature built-in error correction using Reed-Solomon codes, allowing them to remain readable even when partially damaged. They can be scanned from any angle and are widely used for payments, authentication, marketing, and information sharing.
Key Characteristics
- Two-dimensional barcode readable from any orientation
- Supports multiple data types: numeric, alphanumeric, binary, kanji
- Built-in error correction (L, M, Q, H levels)
- High data density compared to traditional barcodes
- Three finder patterns for quick detection and alignment
- Supports various sizes from 21x21 to 177x177 modules
Common Use Cases
- Mobile payment systems (WeChat Pay, Alipay)
- URL sharing and website links
- Contact information exchange (vCard)
- Product tracking and inventory management
- Event tickets and boarding passes
Example
QR Code Data Types:
1. URL: https://example.com
2. Text: Hello, World!
3. vCard:
BEGIN:VCARD
VERSION:3.0
N:Doe;John
TEL:+1234567890
END:VCARD
4. WiFi:
WIFI:T:WPA;S:NetworkName;P:Password;;
5. Email:
mailto:example@email.com