A quick recognition (QR) code is a machine-readable code made of an array of black and white squares. QR codes are read by the camera on a smartphone, and store URLs or other information.
The QR code shown below contains a link to the Bit Trade website.
Open your smartphone’s camera, and hold it in front of the above QR code. You should be prompted to visit Bit Trade’s home page.
QR codes are commonly used in the cryptocurrency space, especially with digital currencies modelled on bitcoin. Payment addresses, cryptographic keys, and transaction information can be shared between digital wallets with QR codes.
Most bitcoin wallet apps allow you to make a payment by scanning a QR code with your smartphone or tablet. This QR code contains all the information required to complete the transaction, including the bitcoin wallet address and, in some cases, the transaction amount.