QR-code was developed in 1994 by the Japanese company Denso Wave. Its appearance was due to the high demands to machine-readable codes imposed by Japanese industry in the 80s. The task of QR-codes is to store large amounts of data in a small area. Any damage or partial code pollution mustn’t interrupt the work of scanning process.

Today, QR-code often can be found in newspapers and advertisements where they contain very long and complex Internet addresses of resources. Any smartphone can recognize and decipher this information. You only need a program to recognize the QR-code. And after it is installed and turned on you just need to place a smartphone camera near the code. Within seconds QR-code program will decrypt it, and then offer to perform a certain action.

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The principle of QR-codes construction

They are always presented in the form of a square. Matrix with the intricate pattern is a heart of the code. Black squares and lines contain the information stored in modules. While the number of modules is directly related to the amount of data that is stored. The smallest code (21x21) includes 441 modules (version 1), and the largest QR-code (177x177) - 31,329 modules (version 40).

In addition, QR-code has additional data that is required for proper recognition of information by special programs on mobile phones.

The construction of QR-code

1. Positioning
   This mark is located in three corners of the picture and allows scanning device recognize the position of the QR-code and scan faster. The width of the white border around the QR-code affects the quality of recognition.

2. The version number
   QR-code also contains information about the version of the code - now their number has already reached forty.

1. Synchronization
   Between the three positional marks, there is the dotted line, which sets the model of the matrix.

2. Format
   With the help of this information, a scanning device specifies the data format. For example, these things are hidden in the code: a calendar record, contact information or a link to a resource on the Internet.

3. Direction
   This mark helps the scanning device to determine whether the image of the QR-code distortion of the perspective or not.

Location of information

The matrix can provide a wide range of options for data storage. Unlike the old samples of barcodes storing of information in matrix might be both horizontally and vertically. For example, squares of small size can accommodate about 4,000 symbols consisting of letters and numbers, combined with special symbols.

The QR-code could be recognized even in the case of damaging or missing the part of the code by means of the error correction system.

The content of QR-codes

The QR-code contains text information in the form of symbols, letters, and numbers. Thanks to this technology, there are various possibilities for text formatting. This allows scanning technology accurately determine the purpose of the code and then suggest the appropriate action.

However, not every QR-code program recognizes all formats. The most common formats are:

• Contact information, which can be applied, for example, on business cards. This helps to simplify the use of personal data, so you simply scan the QR-code and then save the contacts on your computer or phone.

• SMS messages that may be required to participate in the action. Thanks to the QR-code you don’t need to type text. You only need a program for reading QR-codes that allow you see a ready message on the display.

• Internet address that may be in advertisements and newspapers. Through these links, the user can visit the desired sites, without a self-typing in the address bar.

• E-mail address. You do not need to enter data manually, as you can send a letter by pressing a button. These QR-code can be used to obtain information or to participate in some sweepstakes. You can also read the recipient's name.

• Phone numbers. With these codes, you can immediately call a person.

• Geodata that allows seeing the location of the desired object, for example, in Google Maps.

• Text. This format is suitable for a variety of purposes. For example, for application on the travel tickets, as well as for the storage of short poems and texts.

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Now you know everything about QR-code and I want to tell you something really cool!

You can easily create your own QR-code. Given the fact that these codes have not been licensed, anyone can not only use but also create them completely free. You only need a QR-code generator, which is a special program.
If you want to understand how they are created, to begin with, use the free services that are available on the Internet.

You can use:

1. http://goqr.me
2. https://www.the-qrcode-generator.com

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With Love,
Kate

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