What is a QR code: types, history of creation

Today QR codes are found everywhere: on websites, advertising posters, in cafes and restaurants. Outwardly, they look like barcodes and consist of small geometric squares. Using a smartphone, you can use the QR code to go to the site with the necessary information without performing unnecessary actions.

In the article we will look at what is important to know about the QR code, what are its features and meaning, the history of creation, what it looks like, what types there are, what are the differences from the barcode.

QR code: what is it and who invented it

Kewar code - Quick Response (literally "quick response code") - it was designed to quickly decipher the information embedded in it. Initially, many manufacturers put a barcode on their products to automatically read the data and enter it into the database. However, with a large number of goods, this process slowed down, since the barcode can only be scanned at a certain angle, and much had to be done manually.

Who came up with the QR code? The Japanese were the first to think about improving the barcode. In the early 1990s, a subsidiary of Toyota, Denso, began developing a new program that would include more data than a barcode and be subject to rapid decryption. Masahiro Hara, the chief technology officer of Denso, inspired by the logical board game "Go", which requires a board, black and white stones, thought that this was an ideal matrix for placing information. The result of his idea was the appearance of a two-dimensional matrix code, which simplified access to websites. The inventor worked on the innovation for 2 years.

At first, the kewar code was used in the production of cars. But it was important for demanding Japanese consumers to know where the goods were coming from, and gradually the QR code penetrated into other industries. It began to be used in the production of food, medicines, machinery and other goods.

In order to attract other companies to develop, Masahiro decided to open a patent for his invention. So the QR code became widespread all over the world, many enterprises began to use it, and the simultaneous distribution of mobile phones with a camera was the impetus for the invention to "go to the people". Today, everyone can easily create their own kewar code. Read more how to make QR code by yourself in this article.

Why do I need a QR code

Where do I need a qr code? Two-dimensional matrix codes are used everywhere today. They can be found in any sphere of life.

QR code is most in demand:

1. To encrypt Internet addresses that you can quickly access from your smartphone by pointing the screen at a street sign, an advertising poster, product packaging, a guidebook. The email address does not need to be entered, the transition to it is carried out automatically.
2. In the field of passenger transport (ticket numbers are encoded, which are considered by the turnstile or terminal).
3. For non-cash payments. The Chinese were the first to master them, where online payments account for 80% of all transactions. For Russians, SBP (fast payment system) and contactless payments of Sberbank work on this principle.
4. In technical processes. So, at industrial enterprises or in railway depots, a QR code is applied to each mechanism or part. When they are checked, the data is automatically entered into the "checklist".
5. In catering establishments - to switch to a virtual - electronic menu and online orders.

The kewar code gained a new breath during the coronavirus pandemic. Representatives of the People's Republic of China were also the first here to link personal information about citizens to applications with the option of scanning a QR code. When entering places of mass use, a person is obliged to scan a QR code, while information about him is transmitted to the regulatory authorities, which check his contacts with COVID-19 carriers, visits to infected areas or violation of self-isolation.

Alibaba has come up with the program "Health Code", with which you can track the movements of citizens. So, depending on the location (country, district, locality with a large number of infected people) or contact with infected people, a person is assigned a certain status, displayed in a certain color (red, yellow and green). Those who have received a red QR code are considered particularly dangerous and are required to adhere to strict quarantine measures.

The French use a QR code issued by the Ministry of the Interior as a pass that gives grounds to leave the house in self-isolation. When checked by the police, a French citizen is required to present a QR code, which is downloaded before each exit to the street.

Everyone entering Malaysia and Tunisia gets a special bracelet with an individual QR code, which people are required to scan twice a day to inform about their location and health status.

The kewar code helps you quickly translate actions from offline to online. For example, I saw a thing in the store − you can immediately go to the site. Or you can demonstrate an Internet project to someone who holds a business card with a qr code of the advertiser. The QR code gives you the opportunity to buy goods at a discount and the right to cashback, the quest organizers hide hints for players in them.

What the QR code looks like

Externally, the kewar code looks like this: a white square, inside of which are placed small black squares enclosed in double frames − white and black, and small black-and-white modules of different sizes, resembling tetris.

QR Code elements:

1. Indentation in the form of a white border at the edges. This is the boundary that allows the scanner to read the code.
2. Search pattern (black squares at the bottom left, top left and right).
3. An alignment pattern that allows you to read the code even in a distorted form.
4. Synchronization bands are a line in the form of the letter G located between the squares of the search pattern. With their help, even a damaged kewar code is recognized.
5. Version. Located near the upper right square, indicates the version of the code being read.
6. Data cells − all other encoded information (message, link, phone number, etc. p.)

One QR code may contain:

• digits - up to 7089;
• letters - up to 4296;
• hieroglyphs - up to 1817;
• bytes of binary code - up to 2953 (including 2953 Cyrillic letters in Windows-1251 or 1450 letters in Utf-8).

With a small amount of information, some modules will remain empty. The technical part of the code allows the smartphone camera to determine the location and calculate the size of the modules, and also contains the information necessary for code recognition (mask, correction level and version).

Letters, numbers, special symbols, images and sounds are transmitted using QR codes. To encrypt images and sounds, information will have to be compressed as much as possible, so they are not too common. Much more often, a QR code simply gives a link to an image or an audio file.

Information can be encoded horizontally and vertically, so the QR code accommodates so many characters. You can scan data from any angle and even from a damaged code.

The minimum size of the QR code (in pixels) is 21 x 21, the maximum is 177 x 177.

Types of QR codes

There are 2 types of codes − static (reusable) and dynamic (disposable). The first stores data that cannot be changed (text, phone number, link). If you try to edit the information, you will have to regenerate the code, that is, create it again. Statistical kewar codes are used by those who do not need to change information.

Dynamic codes can be edited after they are created without changing the code itself. They are created once, but at any time you can change both the data and the link from which they are displayed.

The QR code has several versions according to the encoding method, but the most used are 4:

1. Digital - for numbers from 0 to 9, makes it possible to write up to 7089 characters.
2. Alphanumeric - for decimal numbers, capital letters, symbols and spaces (up to 4296 characters can be stored).
3. Binary - for ISO-8859-1 encoding (holds up to 2953 characters).
4. Kanji − for Japanese characters of the Shift JIS encoding. It is the least efficient because it stores up to 1817 characters. There is another kanji encoding − ECI, but not all scanners can recognize it.

In addition, there are additional modifications: structured complement mode (which reads up to 16 QR codes) and FNC1, which performs barcode functions.

A QR code can use several encodings at once if the correct version of the code is specified in each.

There is also a classification by appearance:

• the original version of QR is 3 search patterns in the corners;
• Aztec with 1 search pattern in the center;
• MaxiCode with 1 search pattern in the middle, the cells of which resemble a honeycomb;
• PDF417 rectangular shape – the average between QR and barcode;
• Semacode is a data matrix without search patterns.

What is the difference between a QR code and a barcode?

When the QR code was developed, the barcode already existed, but it was imperfect. It was applied to a product or product, so that by translating numbers into sticks it was possible to get information from anywhere in the world (national manufacturer's code, manufacturer's code, product code).

The main difference between a kewar code and a barcode is that the first one allows you to encrypt more information. If a barcode is used to number products, then a QR code is more versatile and allows you to encode not only numbers, but also a lot of other data. At the same time, it is more compact than a barcode, supports a wide set of characters, it can be easily created and printed.

Sometimes mistakes are made in barcodes. They can be noticed when, for example, when buying at the checkout, the scanner shows another product. And the QR code has built-in error protection. Special technologies are required to read and interpret the barcode, and it is possible to decipher the QR code with a conventional smartphone, which makes it more accessible to a wide range of consumers.

A QR code is an affordable way to store any information (texts, email addresses, phone numbers) on a machine-recognizable optical label. The data is encoded using special templates in a square frame, which are read and transformed into user-friendly information using a scanning device built into the phone's memory or a conventional camera on a smartphone.