What Is QR Code? How QR Code Work?

What is QR code?

QR code (abbreviated from Quick Response Code) is the trademark for a type of matrix barcode (or two-dimensional bar code) first designed for the automotive industry in Japan. Bar codes are optical machine-readable labels attached to items that record information related to the item. It was initially patented; however, its patent holder has chosen not to exercise those rights. Recently, the QR Code system has become popular outside the automotive industry due to its fast readability and greater storage capacity compared to standard UPC barcodes. The code consists of black modules (square dots) arranged in a square grid on a white background. The information encoded may be made up of four standardized types ("modes") of data (numeric, alphanumeric, byte / binary, Kanji) or, through supported extensions, virtually any type of data.

How QR code work?

The QR code was invented in Japan by the Toyota subsidiary Denso Wave in 1994 to track vehicles during manufacture. It was designed to allow high-speed component scanning. 

Unlike the older one-dimensional barcode that was designed to be mechanically scanned by a narrow beam of light to extract data, the QR code is detected as a 2-dimensional digital image by a semiconductor image sensor and is then digitally analyzed by a programmed processor. The processor locates the three distinctive squares at the corners of the image, and uses a smaller square near the fourth corner to normalize the image for size, orientation, and angle of viewing. The small dots are then converted to binary numbers and their validity checked with an error-correcting code.

How is a QR Code different from a normal 1D UPC barcode?

Ordinarily we think of a barcode as a collection of vertical lines; 2D Barcodes or QR Codes are different in that the data is stored in both directions and can be scanned vertically OR horizontally.

Whilst a standard 1D Barcode (UPC/EAN) stores up to 30 numbers, a QR Barcode can store up to a massive 7,089! It is this massive amount of data that enables links to such things as videos, Facebook or Twitter pages or a plethora of other website pages.

How do I scan a QR Code?

If you have a smartphone like an iPhone, Android or Blackberry then there a number of different barcode scanner applications such as Red Laser, Barcode Scanner and QR Scanner that can read and decode data from a QR code. The majority of these are completely FREE, and all you have to do once you install one is to use your phone's camera to scan the barcode, which will then automatically load the encoded data for you.

You can use the following file formats when creating a QR Code

HTML Code

PNG File

Tiff File

SVG

EPS

PNG files work particularly well as they can be resized very easily, meaning that you can easily scale the QR Code depending on where you want to put it.

Main uses of QR codes

Originally designed for industrial uses, QR codes have become common in consumer advertising. Smartphone users can install an app with a QR-code scanner that can read a displayed code and convert it to a URL directing the smartphone's browser to the website of a company, store, or product associated with that code providing specific information.

Mobile operating systems

QR codes can be used in Google's Android operating system and iOS devices, as well as by using Google Goggles, 3rd party barcode scanners, and the Nintendo 3DS. The browser supports URI redirection, which allows QR codes to send metadata to existing applications on the device. mbarcode is a QR code reader for the Maemo operating system. In Apple's iOS, a QR code reader is not natively included, but more than fifty paid and free apps are available with both the ability to scan the codes and hard-link to an external URL. Windows Phone 7.5 is able to scan QR codes through the Bing search app.

URL’s

URLs aided marketing conversion rates even in the pre-smartphone era but during those years faced several limitations: ad viewers usually had to type the URL and often did not have a web browser in front of them at the moment they viewed the ad. The chances were high that they would forget to visit the site later, not bother to type a URL, or forget what URL to type. Friendly URLs decreased these risks but did not eliminate them. Some of these disadvantages to URL conversion rates are fading away now that smartphones are putting web access and voice recognition in constant reach. Thus an advert viewer need only reach for his or her phone and speak the URL, at the moment of ad contact, rather than remember to type it into a PC later.

Virtual stores

During the month of June 2011, according to one study, 14 million mobile users scanned a QR code or a barcode. Some 58% of those users scanned a QR or bar code from their homes, while 39% scanned from retail stores; 53% of the 14 million users were men between the ages of 18 and 34.[16] The use of QR codes for "virtual store" formats started in South Korea,[17] and Argentina,[18] but is currently expanding globally.[19] Big companies such as Walmart, Procter & Gamble and Woolworths have already adopted the Virtual Store concept.[20]

Code payments

QR codes can be used to store a bank account information or a credit card information, or they can be specifically designed to work with particular payment provider applications. There are several trial applications of QR code payments across the world.

QR Content

Though typically QR codes identify URLs you can essentially represent any piece of information you like, here are some examples:

Website URL

Send a text message

Send an email message

Address Book record (vcard)

Display some text on your screen

Any bit of text you like

How to Download Google e-books?

Google Books is the greatest public Internet library but it’s not very convenient to read books there. First – the inbuilt reader is odd enough for long reading and contains a lot of distracting elements such as search box, navigation menus, related books, ads that divert your attention. You have to open browser each time you want to read a book at Google Books. Second, you can’t read Google Books when you are offline (there are still many places without internet connection in the world). You can’t print Google Books and read them in bed, but need to sit in front of computer screen that harms your eyes. And you can’t use your favorite E-Book Reader (such as Sony Reader, Kindle or Nook) or a mobile device that provide the most pleasant reading experience. Besides, if you use a book management software (such as Calibre or Alfa Ebooks Manager), where you use to store all your ebook library, you want to download Google Books to your hard drive. Unfortunately, Google doesn’t allow to download any book from Google Books.

But there are still 3 ways to download Google Books to your desktop:

1. Use the Google’s PDF download feature that is available for out-of-copyright books
2. Download books manually from the browser cache
3. Use a Google Books downloader
1. Use the Google’s PDF download feature for out-of-copyright books

For some out-of-copyright books Google Books provide PDF download tool, that allows users to download (and therefore print and read offline) these books. To find books you can download, click on the "Full view books" radio button before entering your search terms. Clicking on the "Download" button shown on public domain books will allow you to download a PDF of the book to your computer. Unfortunately, not all books that are fully viewable are downloadable as PDF files. The overall number of books with the full preview there is much larger.
2. Download books manually from the browser cache

The book pages that you can view in Google Books are presented as PNG images on the HTML page. So, it is possible to save any visible book page as an image to your computer. You can "save page as" in any browser and find the PNG image in the saved "files" folder. But you need to scroll the book and repeat this "save page as" operation for each page.

To make this process a little easier, you can use Internet Explorer (not Firefox). You can use the following wizard:
1. Open folder “C:\Documents and Settings\%USER%\Local Settings\Temporary Internet Files\” of your computer machine and delete all of the content of the folder
2. Open the needed book at Google Books in Internet Explorer and scroll it down to the end (or use the page browser).
3. Open “Temporary Internet Files” folder. Copy all PNG files. These files are the pages of the scanned book
4. Now you can print the PNG files and arrange them in order for reading OR use a PDF compiler tool to create a single PDF file from multiple PNG images
3. Use a Google Books downloader

There are some tools that automate the routine operations described in the previous paragraph. But unfortunately, most of them don’t work properly – they either download only few book pages, or hang your computer, or cause ban of your Google Account. The most popular tool that was called Google Books Downloader was recently terminated by its creator. For now, the only tool that is recommended for 

downloading Google Book is GooReader.

Though the primary feature of this small program is a comfortable book viewer that allows to read Google Books on your desktop, it also can convert Google Books to PDF files and save them on your computer. It works quite fast and can download a 300-pages book in few minutes. It also includes the inbuilt Google Books Search tool that shows, which books have a full view, partial preview or no preview. You also can view the number of available pages of each book. Besides, it doesn’t require you to log in your Google Account, so it’s no risk that it could be banned. You can download GooReader here.