QR code (Quick Response code) is the trademark for a type of matrix barcode (or two-dimensional barcode) first designed in 1994 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. In practice, QR codes often contain data for a locator, identifier, or tracker that points to a website or application. A QR code uses four standardized encoding modes (numeric, alphanumeric, byte/binary, and kanji) to store data efficiently.

The Quick Response system became popular outside the automotive industry due to its fast readability and higher storage capacity compared to standard UPC barcodes. Applications include product tracking, item identification, time tracking, document management, and general marketing.

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

HOW TO READ A QR CODE

Open the QR Code reader on your phone.

1. Open the QR Code reader on your phone.
2. Hold your device over a QR Code so that it’s visible within your smartphone’s screen.
3. If necessary, press the button to visit the URL.

Your smartphone reads the code and navigates to the intended destination, which doesn’t happen instantly. It may take a few seconds on most devices.

On the latest iOS and Android smartphones, the QR Code reader is built-in on the camera. So you don’t need an extra reader app, open the camera and point it to the QR Code.