What is a QR Code? Types, Benefits, and Security Explained

A QR code (Quick Response code) is a two-dimensional barcode that stores information in a pattern of black and white squares, which a smartphone camera can read instantly. The information can be a website link, contact details, or payment details. When you scan a QR code at a shop, your payment app reads the merchant’s details and prepares the payment within seconds.

Originally developed in Japan in 1994 for tracking automotive parts, QR codes have become an essential part of India’s digital payment ecosystem. Today, they are used everywhere, from large retail stores to neighbourhood kirana shops. This guide explains how QR codes work, the different types you’ll encounter, their benefits, and how to use them safely.

How Does a QR Code Work?

The process is simple. A QR code stores data both horizontally and vertically, which is why it can hold far more information than the striped barcodes on product packaging. When you point your phone’s camera at a QR code, the scanner reads the pattern, decodes the stored information, and performs the relevant action, such as opening a website, saving a contact, or preparing a payment with the merchant’s details already filled in. 

QR codes are also built to be reliable in real-world conditions. Thanks to built-in error correction, a code remains scannable even if up to 30% of it is faded, scratched, or partly covered, which is why the sticker at your local shop keeps working through months of sun and rain. They can also be scanned from any angle, so you never need to align your phone perfectly.

QR Code vs Traditional Barcode

What are the Types of QR Codes?

• Static QR codes: The information is fixed permanently when the code is created and cannot be changed later. The payment QR sticker at a shop is a static QR: it always points to the same merchant account, and the customer enters the amount while paying. Static QRs are free to generate and can be printed once and used for years.
• Dynamic QR codes: The information behind the code can be updated, and in payments, a dynamic QR is generated fresh for each bill with the exact amount embedded. When you scan one at a supermarket counter or on a card machine’s screen, the amount appears pre-filled, which removes entry errors and speeds up the queue.
• UPI QR codes: The standard payment QR in India, built on NPCI’s UPI system. The most useful thing to know about UPI QRs is that they are fully interoperable: any UPI app can scan and pay any UPI QR, regardless of which app’s branding appears on the sticker. A Paytm QR works with every UPI app, and Paytm’s scanner works with every UPI QR.

What are QR Codes Used For?

• Payments: QR codes have transformed digital payments in India by allowing customers to pay merchants instantly without entering bank details. Businesses of every size, from supermarkets to roadside vendors, can accept digital payments using a printed QR code. 
• Receiving money: Every UPI user has a personal QR code in their app. Sharing it is the easiest and most error-proof way to receive money, since the sender’s app picks up your details directly from the code with no typing involved.
• Business operations: Merchants use QR codes to accept payments, and devices like the Paytm Soundbox announce each received payment aloud, giving instant confirmation without checking a phone. QR-based payments also create a digital record of every sale, which helps with accounting and even loan eligibility for small businesses.
• Information sharing: Beyond payments, QR codes appear on tickets and boarding passes, restaurant menus, product packaging, event registrations, Wi-Fi sharing, and app download links.

What are the Benefits of QR Codes?

• Speed: A scan takes a second or two, and the payment or information is ready instantly, with no manual entry.
• Accuracy: Details are read directly from the code, so there are no typing errors in account details or links.
• Low cost: Static QR codes are free to create and can be printed on ordinary paper, which is why even the smallest businesses can accept digital payments.
• Durability: Error correction keeps codes working even when partly damaged or faded.
• Contactless convenience: The entire interaction happens from your own phone, with nothing to touch or hand over.
• Interoperability: UPI QR codes work across all UPI apps, allowing customers to pay using the app of their choice without worrying about compatibility. 

How to Scan and Pay Using a QR Code on Paytm

Using a QR code on Paytm is quick and secure. Once your bank account is linked to UPI, you can pay any UPI QR code in just a few steps.

Step 1: Open the Paytm app and tap Scan & Pay on the home screen.

Step 2: Point your camera at the merchant’s QR code. You can also choose Scan from Gallery if the QR code is saved as an image on your phone.

Step 3: Verify the recipient’s name displayed on the screen before proceeding.

Step 4: If the amount isn’t already filled in, enter the amount you want to pay.

Step 5: Select your preferred payment method, such as your linked bank account, UPI Lite (where available), or an eligible RuPay Credit Card on UPI for merchant payments.

Step 6: Tap Pay and enter your UPI PIN to complete the transaction.

Once the payment is successful, Paytm shows a confirmation screen along with the UPI Reference Number (UTR), which you can use to track the transaction or raise a support request if needed.

Tip: Always check the recipient’s name before entering your UPI PIN, and wait for the payment confirmation before leaving the merchant.

How to Use QR Codes Safely

QR payments are designed to be secure. Scanning a QR code only reads the information stored in it. Your money leaves your account only after you verify the recipient and authorise the payment using your UPI PIN. 

• Check the name after scanning. When you scan a payment QR, the app shows the verified name of the person or merchant receiving the money. A quick glance to confirm it matches the shop ensures your payment goes exactly where intended.
• Scan payment QRs you can trust. QR codes displayed at shops and shared by people you know are the normal, safe use. For codes received from unknown sources online, verify the name on screen before proceeding, and remember that receiving money never requires you to scan a code or enter your PIN.