A Quick Response Code (QR Code) is a type of matrix barcode (or two-dimensional barcode) that can be scanned using a smartphone or a QR scanner to quickly access information or perform actions. QR codes contain data in a square grid of black and white squares, which can represent various types of information, such as URLs, contact details, or text. When scanned, the encoded information is instantly retrieved and used to direct the user to a website, download an app, add a contact, or complete other actions without the need for manual data entry.

QR codes are widely used in marketing, payments, product tracking, and authentication, providing a simple and convenient way for consumers to interact with digital content. For example, businesses often use QR codes in advertisements to direct customers to their websites or promotional offers. In the context of mobile payments, QR codes enable quick and secure transactions by linking to payment apps. QR codes are also used for contactless entry systems, event check-ins, and verifying the authenticity of products. Their versatility and ease of use have made QR codes a popular tool for bridging the gap between the physical and digital worlds.