QR codes: barcodes you can scan with a mobile phone

QR codeQR codes are small, pixellated black and white squares, similar to barcodes. The QR code can be scanned using a camera built into a mobile phone to reveal a message, view information, or direct people to a website

QR codes have long been used in Japan on everything from vending machines and posters to business cards and shop windows. They are now commonplace on adverts, posters, packaging and more in the UK too. Most businesses use QR codes as a marketing tool.

So what are QR codes, how do they work and should your business be using them?

QR codes for beginners

Steve O’Connor is a designer at Airsource, a mobile development agency based in Cambridge that’s built a QR code reader for iPhones. “A QR code is a two-dimensional barcode,” he explains. “It contains information both horizontally and vertically within its pattern.”

“QR codes can be used to hold any kind of written data and transfer it instantly,” he continues. “It could be a message, a link to a video, a coupon or special offer, co-ordinates of a particular location – the list is growing bigger all the time!”

The most common way to read QR codes is to snap them using a mobile phone camera. Most smartphones can do this. Special applications (apps) can be downloaded to read the information contained in the QR code. Apps to read QR codes are available for most smartphones, including iPhones and Android devices.

“Point your camera at the code and the app should translate the pattern into data,” explains O’Connor. “It will usually recognise what kind of data it is and react accordingly. For instance, if it’s a web address it will take you to there. If it’s someone's contact details, it will ask if you want to add them to your address book.”

The purpose of QR codes

QR codes are often used as a bridge between offline and online locations. For instance, putting one on a restaurant menu or in a shop window can help drive real-world customers to your website (for this to be most effective, send them to a special page designed for mobile phones).

O’Connor says there are lots of other innovative ways to use QR codes too: “You can have a QR code as your ticket for an event. It could contain a utility bill or be used for taking and making payments - all securely of course.” In fact, in Japan, you can pay for items in some vending machines by scanning a special QR code.

You can store quite a lot of information in a single QR code. “Although in principle you can store up to 3kbs of data, the practical capacity when used with mobile phone cameras is around 400 characters,” explains O’Connor “This ensures the codes are not too dense and can be scanned easily.”

Do people understand QR codes?

It’s easy for your business to create QR codes. And they work well – even poor-quality photos of QR codes can usually be decoded. But if people don’t understand how to use them, is it worth the effort?

Well, frankly the jury's still out. Some surveys suggest people are confused by QR codes, but marketers have embraced them wholeheartedly. Some smartphones can recognise and decode QR codes automatically (without requiring a third-party apps), and as this function becomes more widespread, it's likely QR codes will become more widely used.

Get started with QR codes

As creating QR codes is quick, easy and free, why not try it for yourself? See: how to create a QR code.

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