how do qr barcodes work

QR code - Wikipedia, the free encyclopedia


** QR code **

From Wikipedia, the free encyclopedia
Jump to: navigation, search
This article is about the type of barcode. For the mathematical coding
theory, see Quadratic residue code.
QR code for the URL of the English Wikipedia Mobile main page

*QR code* (abbreviated from *Quick Response Code*) is the trademark for a
type of matrix barcode (or two-dimensional barcode) first designed for the
automotive industry in Japan. A barcode is a machine-readable optical label
that contains information about the item to which it is attached. A QR code
uses four standardized encoding modes (numeric, alphanumeric, byte /
binary, and kanji) to efficiently store data; extensions may also be

The QR Code system became popular outside the automotive industry due to
its fast readability and greater storage capacity compared to standard UPC
barcodes. Applications include product tracking, item identification, time
tracking, document management, and general marketing.^[2]

A QR code consists of black modules (square dots) arranged in a square grid
on a white background, which can be read by an imaging device (such as a
camera, scanner, etc.) and processed using Reed–Solomon error
correction until the image can be appropriately interpreted. The required
data are then extracted from patterns that are present in both horizontal
and vertical components of the image.^[2]


· 1 History
· 2 Standards
· 3 Uses

· 3.1 Mobile operating systems
· 3.2 URLs
· 3.3 Virtual stores
· 3.4 Code payments
· 3.5 Website login
· 3.6 Funerary use
· 3.7 Encryption

· 4 Design

· 4.1 Storage
· 4.2 Error correction
· 4.3 Encoding
· 4.4 Decoding example

· 5 Variants
· 6 License
· 7 Risks


© 2005-2018