QR Codes: Origin, How They Work, and Why They Matter
The Origin of QR Codes
The QR code — short for Quick Response Code — was invented in 1994 by Masahiro Hara, an engineer at Denso Wave, a subsidiary of Toyota in Japan. At that time, automotive factories were filled with thousands of tiny parts, and tracking them using traditional barcodes became inefficient. Barcodes could only store a few digits and had to be scanned one by one, always in a horizontal direction.
To solve this problem, Hara’s team designed a two-dimensional code that could be scanned instantly from any direction and could hold hundreds of times more data than a standard barcode. That’s how the modern QR code — now found everywhere from restaurant menus to airline tickets — was born.
How QR Codes Store Information
A QR code is made up of a grid of black and white modules (dots) arranged in a square pattern. Each black dot represents a binary 1, and each white space represents a binary 0. Together, these dots form a binary language that computers can read and decode.
The arrangement of these dots is not random — it follows strict encoding rules defined by international standards (ISO/IEC 18004). This encoding allows QR codes to store a variety of data types, including:
- Numeric data (digits only)
- Alphanumeric data (letters and numbers)
- Kanji or UTF-8 characters (for Asian languages)
- Binary or special symbols
The more dots (modules) a QR code contains, the higher its version and the more data it can store. For example, a Version 1 QR code (21×21 modules) holds about 25 alphanumeric characters, while a Version 40 QR code (177×177 modules) can store over 4,000 characters.
How a QR Code Is Read
When you scan a QR code with a camera or a dedicated reader, the device captures the pattern of black and white modules. Then, using built-in algorithms, the scanner:
- Detects the orientation of the QR code.
- Locates the finder patterns — the three large squares in the corners — which act like landmarks.
- Analyzes timing patterns to understand how the modules are spaced.
- Reads the data region and converts the arrangement into binary code (0s and 1s).
- Decodes the binary code into numbers, letters, or symbols.
Because of the finder patterns, a QR code can be read from any angle — even if it’s upside down, tilted, or partially damaged.
To make QR codes reliable in real-world conditions, they also include error correction based on Reed–Solomon algorithms. This means even if 30% of the code is smudged, scratched, or covered, the scanner can still reconstruct the original data.
What Can a QR Code Contain?
Originally created for inventory tracking, QR codes are now used for almost every digital interaction imaginable. They can store and share:
- Website URLs — for example: https://funifytools.com
- Wi-Fi login information, allowing instant connection without typing a password
- Contact details (vCards) or phone numbers for quick dialing
- Google Maps locations or event invitations
- Payment information for mobile transactions (used widely in QR-based fintech apps)
Because a QR code is just an image, it can be printed on paper, displayed on screens, or embedded into products. Once scanned, it bridges the physical and digital worlds, instantly linking a user to an online experience.
Why QR Codes Matter Today
In today’s connected world, QR codes have become a universal access point for information. They are fast, contact-free, and platform-independent, working on virtually any smartphone or camera-equipped device.
During the pandemic, QR codes became essential for contactless menus, check-ins, and payment systems, proving their convenience and flexibility.
Beyond simple links, modern QR codes can also be custom-branded, include logos, and be color-coded while remaining fully scannable — a sign of how this simple 1990s invention continues to evolve.
Summary
In essence, a QR code is a square digital fingerprint — a precise pattern of dots encoding data into machine-readable form. Behind its simple appearance lies mathematical structure, error correction, and data compression — all working together to make information instantly accessible.
From tracking car parts in Japanese factories to linking users to websites like Funifytools.com, the QR code has become one of the most versatile and enduring tools of the digital age.
You can view the original blog post in Korean at the links below: