The term "QR code" is a compound noun. It is an abbreviation for Quick Response code, a registered trademark for a type of two-dimensional matrix barcode. Its primary function is to store information in a machine-readable optical label that can be rapidly interpreted by an imaging device, such as a digital camera or smartphone.
Unlike a traditional one-dimensional barcode which encodes data horizontally, this matrix format stores information both horizontally and vertically. This structure grants it a significantly higher data storage capacity, capable of encoding numeric, alphanumeric, binary, and Kanji characters. Key structural elements include three distinct square finder patterns at the corners, which enable high-speed, omnidirectional reading, and alignment patterns that correct for distortion. A critical feature is its implementation of the Reed-Solomon error correction algorithm, which allows the data to be successfully read even if a portion of the code is damaged or obscured.
In application, this technology serves as a direct interface between the physical and digital worlds. It is widely employed in marketing to link print advertisements to websites, in contactless payment systems to initiate transactions, for ticket verification, and to provide instant access to product information or Wi-Fi networks. Its utility lies in its ability to offer a low-cost, easily deployable method for encoding and retrieving data, effectively functioning as a physical hyperlink to a digital resource or action.
