A shop needs a QR code inorder to uniquely identify a product. QR codes works in the same way as a barcode as it can be scanned and interpreted by another device. The advantages of a QR code are as follows: 

• They help the seller to stand out from the crowd 
• Let's you target customers on the go in the sense that it's easier for prospects and customers to access your information quickly on their devices. 
• They are free and easy to setup 
• They are interactive