QR Code (Quick Response Code): A special type of two-dimensional bar code that stores information in a machine-readable form. QR codes consist of black and white squares arranged in a square grid that can be scanned with a camera, such as the camera on a smartphone. They can store a variety of data, including text, URLs, contact information, location coordinates and more. QR codes are widely used in marketing, ticketing, product tracking and many other applications where quick access to information or digital resources is needed. They have the advantage of being easy to create and use, have high error tolerance, and can store a larger amount of data than traditional barcodes.