What is a QR Code and how does it work?

Quick Response QR Code

QR code looks very simple, but it has a wide range of functionalities. QR code stands for quick response code as it allows instant access of information to the users. Without waiting for a minute, let’s discuss QR in depth!

What is a QR code?

A QR code is a square-shaped grid having alphanumeric information that can be read with a digital machine. In a supply chain process, a QR code is widely used to track product’s information. In order to decode the QR code, QR scanners work perfectly fine, but you can use a QR code scanning application on your mobile.

Many smartphones such as Xiaomi, iPhone, and Samsung come with built-in QR scanning cameras.

In 1994, Denso Wave, a Japanese company, first invented the QR code system. This company was a subsidiary of Toyota. The purpose of that QR system was to track vehicle parts more accurately during the manufacturing process. A type of barcode was developed to encode alphanumeric, kana, and kanji characters to accomplish this purpose. After that, they declare their QR code as open-source that means anyone can use that codes.

The first mobile QR scanner was developed in 2002 in Japan. The purpose of this invention is to increase the trend of using QR codes.

Reading direction of standard barcodes is only from top to bottom that allows storing a small amount of data in an alphanumeric structure. QR codes can store more information as they can be read from right to left and top to bottom. 

You can add phone numbers, texts up to 4000 characters, and URLs. Moreover, you can perform many other tasks with QR code such as:

  • Making payment transactions
  • Adding link that directly downloads your app from Google Play store or Apps store
  • Accessing Wi-Fi through storing some information such as service set identifier SSID, passwords, and encryption type
  • Online authentication of accounts and login through QR system
  • In the UK, a company created QR codes and put them on the gravestone to scan and read an online story about the person (if he has an online story)

How does QR code work?

A standard QR code is identified on the basis of three squares placed outside the QR code. After identifying these squares, the QR reader knows that the QR code is inside the square.

The QR reader breaks the entire block into a grid and starts analyzing the code. It checks whether grid square has black or white color and assigns values according to color. After that, it creates a large pattern by grouping all the grid squares.

What are the parts of a QR code?

There are six components to identify a standard QR code:

Quiet Zone: It is a white border outside the QR code. Without this border, the QR reader gets interfered with outside elements and can’t get information inside the QR code

Finder Pattern: There exist three squares in the QR code. The purpose of these square is to let the reader know about the boundaries of code

Alignment Pattern: It is a small square placed on the bottom right corner. It helps to read the code even if it is placed at an angle

Timing Pattern: There is an L-shaped line between three squares called a timing pattern in the finder pattern. This line aims to identify each square in the code that makes it possible to read damaged QR codes.

Version Information: On the top-right finder pattern cell, there exists a small field of information. Version information tells about the version of the QR code.

Data cells: QR code has many data cells that contain actual information such as phone number, URL, and any text message

How do I scan QR codes?

The latest smartphones have built-in QR scanners or cameras to scan QR codes. If you want to scan code in old mobiles, you need to install a particular app from Google Play Store or App Store. QR code scanning is deadly simple from mobile:

  • Open the camera or QR scanner application in your mobile
  • Point the reader at the code to get necessary information
  • After reading the data, it may show it on a mobile screen

Can someone hack a QR code?

It is impossible to hack QR codes, but your QR code destination can be hacked through QR code.

Always scan a trusted QR code because it might be a malicious code that steals your personal information or track your location.

Quick Response (QR) Codes vs. Barcodes

Traditionally, the amount of information that could be conveyed about a product or service was limited by the amount of space available on the product’s packaging or in the advertisement touting its benefits. If a customer wanted more information about the product—availability, price, or attributes had to find a salesperson or request additional documentation.

Barcodes are commonly found on the back of product packages and convey data by combining various widths of parallel lines that can be read by machines equipped with an optical scanner.

The barcode revolutionized the way businesses managed inventories and pricing, and it was first used in practice by US railroads to track equipment and containers in the 1960s. Traditional two-dimensional barcodes became widely used in retail stores in the United States in 1974. From employee ID badges and hospital bracelets to shipping containers, barcodes can now be found on almost everything.

Types of Quick Response (QR) Codes

There are several types of QR codes that can be used for different purposes. They are as follows:

  • Micro QR Code: When space is limited, a smaller version of a traditional QR code is used. The smallest micro QR code is 11 x 11 modules, which can encode up to 21 alphanumeric characters.
  • Model 1 QR Codes: Model 1 is the Model 2 and Micro QR prototype. The Automatic Identification Manufacturers International (AIMI) standard recognizes one to 14 versions. It has a maximum data capacity of 468 bytes, which allows it to encode up to 707 alphanumeric characters.
  • Model 2 QR Codes: Model 2 has a better alignment pattern for position adjustment and more data density than Model 1. The AIMI standard has one to 40 versions, with version 40 capable of storing up to 4,296 alphanumeric characters.
  • IQR Code: In cases where space or shape is an issue, it can be created in squares or rectangles. It can be in any of 61 different formats.
  • SQRC: Features a restricted reading function to contain private information.
  • Frame QR: Customizable frame that can contain larger data in formats such as graphics, illustrations, or photos.


QR codes come with many functionalities. You may experience scanning QR codes in the restaurant to get the menu items. However, it is widely used in many marketing campaigns, organizations, and supermarkets.

See Also
What is IPTV
Difference Between 4G and 5G Networks