Life in the 21st Century is unthinkable without scanning a QR Code. Chances are you must have scanned a QR Code hours before you read this. But what is this square you see slapped all around—from a birth certificate to a gravestone? Come with us as we uncover everything you ever needed about the QR Codes—in unprecedented detail.
What is a QR Code?
A QR Code, or Quick Response Code, is a type of barcode that can contain data such as website URLs, calendar events, PDFs, images, or anything you can host online. You can scan a QR Code with a mobile device camera to access the data.
In modern marketing and the digital era, businesses and individuals use QR Codes as a bridge to connect their offline and online worlds. Thanks to technology, modern QR Codes do much more than link to websites. It’s possible to use them as end-to-end marketing tools to improve customer experience, collect first-party data, and improve business outcomes.
A brief history of QR Codes
The QR Code was invented in 1994 by a Japanese engineer, Masahiro Hara, as an alternative to the stripped barcode. Their initial purpose was to track car parts in large-scale manufacturing units.
The early 2000s saw QR Codes infiltrating consumer goods. They began appearing on product packaging, advertisements, and even business cards. The gradual integration into everyday life increased public familiarity with these square barcodes (QR Codes are an updated version of the regular barcode you see in product packaging).
A major breakthrough for QR Codes happened in 2017 when Apple and Google incorporated QR Code scanning as a native feature in their mobile operating systems. This made it incredibly easy for people to use QR Codes, eliminating the need for dedicated scanning apps.
On the 50th anniversary of barcodes, GS1—a non-profit that standardizes barcodes for global industries—announced “Project Sunrise 2027.” It was an action plan for a global transition to QR Codes by 2027 from barcodes because of their inherent benefits for businesses and consumers.
Want to know the entire history behind this fascinating technology? Here’s the history of QR Codes—from 1994 to 2024—in under 10 minutes.
How does a QR Code work and store data?
A QR Code works by storing data in binary codes (the patterns or pixels you can see). Binary is a coding language that uses “0” and “1” (also called bits) as symbols to represent other characters in computers.
Combining these bits can represent any information—from a simple text message to a complex URL—or even lead to a website or a video. This explains why you can view any content from a QR Code.
When you scan a QR Code with your mobile device, this pattern is decoded back into binary code to reveal the information it contains. Then, it converts that binary code into the intended information, such as a website link, a contact, or text.
While QR Codes may appear to contain a random combination of patterns, each QR Code is unique and distinct. You can further customize it with different colors, frames, shapes, and logos using a QR Code generator.
📗Note: While you can customize the shape of the QR Code, the area where your QR Code data will be stored must always be within a square.
There are two main types of QR Codes: dynamic and static:
- You cannot change static QR Codes once created and cannot track their data
- You can edit dynamic QR Codes as many times as possible and track their data to measure their performance
Learn: The differences between dynamic and static QR Codes
Elements of a QR Code
A QR Code is a clever technology that takes cues from its close brethren, the 1D barcode, while including some novel and unique elements.
Here’s a breakdown of every element in a QR Code and what role they play:
1. Position marker
Note three squares on the outer edge of a QR Code. These are like compass points on a map. When you scan a QR Code, your mobile device identifies these markers to orient the QR Code and let you scan from any angle. They are also called the eyes of a QR Code.
2. Alignment marker
It is the fourth square with a dot, but not on the outer edge of a QR Code, such as position markers. It acts as the camera’s focus point. It also acts as a buffer position marker and helps orient the QR Code image in case the larger ones are obscured or blurry.
3. Timing pattern
These dots or pixels run only between two position markers in the corner of a QR Code. These patterns help your camera determine how big the QR Code is and where each position marker is.
4. Quiet zone
You must have noticed a clear space around the outer edges of a QR Code. This is called the quiet zone—the most crucial part of the QR Code as it helps the scanner differentiate the QR Code from the surroundings.
5. Version information
There are over 40 different types of QR Codes. The version information is like the table of contents in a book—it helps the scanner understand how to interpret the entire code. It is located in two places near any two-position marker, depending on the QR Code’s orientation.
6. Format information
This is located on the edges of three position markers. The format information helps point out the error-correction level and mark pattern or how the data is arranged. Ultimately, this makes the QR Code easier to scan and interpret.
7. Data and error correction module
This is the central part of a QR Code where the data is stored. It consists of most data modules or the pixel-like dots in the QR Code. Error correction module is the extra dots that help scan a QR Code even if some data module is missing. You cannot identify the data and error correction modules because they are mixed with other elements.
What happens when you scan a QR Code?
When you scan a QR Code with your mobile device, a few key things happen behind the scenes to quickly decode the information stored in that pattern of black and white squares:
Are you having trouble scanning a QR Code with your native camera app? Check out our detailed guides on scanning QR Codes on Android and iOS.
Are QR Codes safe?
Yes, QR Codes are safe. However, as with any technology, threat actors can misuse them to cause harm, forcing the FBI to issue awareness warnings.
Due to their simplicity and accessibility, people have learned to scan and trust them unquestioningly without following safety practices. This has led to a rise in QR Code phishing scams such as these:
Quishing
This is phishing using a QR Code (hence the portmanteau,“quishing”). This is one of the ways a QR Code is being misused lately via email phishing scams.
Threat actors put QR Codes linked to malicious websites in emails pretending to be from legitimate sources and for critical reasons.
Sticker-swapping
QR Codes can be misused by superimposing a QR Code linked to a malicious site on a legitimate QR Code in physical locations such as parking lots, posters, etc.
You might fall into a scammer's trap if you fail to recognize the sketchy QR Code stuck to a legitimate one.
QRLJacking
Bad actors can create a fake version of a “log-in with QR Code” page (including a fake QR Code that can harvest data). They bank on this log-in method many organizations offer as an alternative to standard ways of logging in.
You may receive the fake page with a malicious QR Code via emails, messaging apps, and other means. Scanning the QR Code will log you into the attacker’s phony session, leading to access to your sensitive data and account hijacking.
Best practices to prevent QR Code scams
What are the advantages of a QR Code over a barcode?
QR Codes are two-dimensional barcodes that store data vertically and horizontally, whereas traditional barcodes only store data in horizontal lines (hence one-dimensional). Being 2D helps store more data and makes QR Codes scannable from any direction.
Because QR Codes were invented to address the limitations of traditional barcodes, they have several advantages over them, which are: