An Introduction to QR Codes

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Likely you've seen QR codes everywhere. Let's take a look at what these codes are, how they work and how they are used.

If you’re not familiar with Quick Response Codes (QR codes), it’s likely that you’ve noticed the strange, pixelated black-and-white squares popping up all over the place – online, in newspapers and magazines, on store windows and even on T-shirts. Here we’ll take a look at what these codes are, how they work and how they are used.

What Is a QR Code?

A QR code is much like a bar code, except that because it carries data in two dimensions (horizontally and vertically), it is able to hold much more information than a one-dimensional bar code. In fact, compared to a bar code’s 20 alphanumeric character limit, a QR code can hold thousands of characters of data. As a result, a QR code can be used to share multimedia content, a landing page or an entire e-book. However, QR codes can do much more than that – they can actually direct a phone to perform certain actions. For example, a theatre company might provide a QR code that not only sends the person who scans it to the company’s website for show times and ticket information, but also embeds information about the dates, times and locations of upcoming shows into the phone’s calendar.

QR codes were designed by DENSO WAVE in Japan and first came into use in 1994. Although the term “QR code” is a registered trademark, the technology itself has not been patented and is therefore available for anyone to use. One key benefit of these codes for the Japanese is that they are one of the most efficient ways of encoding Japanese characters. However, their high data capacity, small print-out size and resistance to dirt and damage (QR codes can still be read when up to 30 percent of the code has been corrupted) ensured the proliferation of this technology to other applications. In addition, unlike bar codes, which can only be read by a special scanner, many smartphones are able to scan QR codes, making them an excellent way to provide large amounts of information in a very small space. (To learn more about mobile computing, see Should Your Business Go Mobile?)

How QR Codes Work

In the simplest terms, data can be translated into a QR code through a QR code generator, many of which are available online for free. Users enter the data they wish the QR code to display, and the generator turns it into a symbol that can be printed or displayed in electronic form. Scanning applications for reading QR codes can be downloaded (often for free) to smartphones, allowing users to simply point the phone’s camera at the code to scan it. The application then interprets the code and implements the data from the QR code by displaying a web page, playing a video or providing some other type of content.

How QR Codes Are Used

So far, QR codes have generally been applied to marketing and building online community, but they are also being tested in more formal settings such as government and academia.

For example, a business can produce a QR code that links a mobile device to a fully-functioning Facebook “Like” page. For brick-and-mortar businesses, this can be a good way to build online presence and provide a contextual call to action to customers. (QR codes can even be used in payments now. For more on mobile payments, see Cache, Text or Direct Bill: The Truth About Mobile Payment Systems.)


Another way QR codes have frequently been used by brick-and-mortar businesses is to provide an additional digital component to a customer’s experience in a brick-and-mortar store. For example, one retailer of Christmas merchandise provided a QR code on its storefront window, behind which a moving display of toys, trains and teddy bears was featured. The QR code launched the soundtrack for the visual display, providing a more integrated and interactive experience for window shoppers – and hopefully one that would move them to come inside!

According to a report by Educase Learning Initiative, a community of universities, colleges and other organizations committed to advancing learning through innovations in IT, QR codes support “experiential learning” by providing students with referential online resources outside the classroom. QR codes may also be used on campus such as in equipment rooms, where they might be used to access a how-to manual for the equipment, or in libraries, where the QR code could be included in a book and encode a phone number or web page for renewing the book.

The Future of the Code

Although QR codes are most popular in Japan and South Korea, their popularity is growing in the U.S. and Europe as businesses and individuals continue to come up with new and creative ways to use them. QR codes also represent another step away from the use of keyboards as input devices in mobile computing, so although the technology and uses for QR codes are likely to evolve, the new direction in mobile computing they represent is likely to continue.


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Tara Struyk
Tara Struyk

Tara Struyk is the VP of Content at Janalta. She has contributed to starting a number of verticals from the ground up, including content research, selection, hiring, editorial guidelines and oversight, and setting up social media and content marketing. She began her career as an editor at Investopedia and eventually moved up to senior editor, where she managed a team of five other editors and more than 200 freelance writers. She has also worked as a freelance financial writer and content manager.Tara earned her Bachelor of Science in journalism and Bachelor of Arts in English literature from the University of…