What Is a QR Code?

A QR code is a type of bar code designed for use with smart phones and other devices that contain cameras. QR codes can contain much more information than a standard UPC-style bar code, and are therefore useful for directing users to websites and other online information. Any modern smart phone can interpret and use QR codes.


A QR code appears as a black-and-white square containing three smaller alignment squares and a random-looking pattern of dots. The alignment squares, which are located in the corners of the larger square, help the QR reader to focus in on the code. The pattern of dots contains the actual information for the QR code. QR codes can, technically speaking, be any size; however, to make it easier for smart phones to read them, most QR codes are at least 1.25 inches by 1.25 inches.

Advertising and Marketing

QR codes often appear in advertising and on consumer products. A car advertisement on a bus shelter, for example, might contain a QR code; when a passerby takes a picture of the QR code using a smart phone, the code opens the phone's browser and takes the user to a website detailing the car's specifications and price. Many coffee and wine companies include QR codes on their products' packaging; when the user scans the QR code, her phone opens a website that shows where the coffee beans or grapes originated.

Other Uses

Because a QR code can contain virtually any type of information, it has many uses beyond advertising and marketing. Some conveyor-belt sushi restaurants, for example, put a QR code on each plate on the belt, and then set up a camera that reads the QR codes as they go by. If the camera detects that a certain plate of sushi has been on the belt for too long, it alerts the restaurant staff. QR code t-shirts allow people to view others' social networking profiles by simply pointing a smart phone at the shirt, while QR codes on historic landmarks can open audio tour clips on the users' phones.

Accessing QR Codes

To take advantage of QR codes, you'll need a QR reader app like NeoReader for the iPhone, Blackberry Messenger 5.0 for the Blackberry or QR Droid for Android-based smart phones. Download and install the app on your phone; then launch it and point the camera at a QR code. If the app has a "Scan" button, tap it; otherwise, just hold the phone so that the QR code fills the screen. When the app recognizes the QR code, it launches a Web browser on your phone and takes you to the link contained in the code, or opens the information associated with the QR code.