A 2D code, also known as a QR (Quick Response) code, is a type of barcode that can store information in two dimensions. Unlike traditional barcodes, which contain only a vertical pattern of lines, QR codes contain both vertical and horizontal patterns, allowing for a greater amount of data to be stored in the code. QR codes can be scanned by smartphones, tablets, and other devices equipped with a camera and QR code reader software, allowing users to quickly access information or links to websites without typing in a URL. QR codes are increasingly used in marketing and advertising campaigns, as well as in industries such as transportation, healthcare, and food service to provide quick access to data or instructions.