QR Code is 2-D (two-dimensional) symbology developed by Denso Wave (a division of Denso Corporation at the time) and released in 1994 with the primary aim of being a symbol that is easily interpreted by scanner equipment.

Small Printout Size
Since QR Code carries information both horizontally and vertically, QR Code is capable of encoding the same amount of data in approximately one-tenth the space of a traditional bar code. (For a smaller printout size, Micro QR Code is available)
Dirt and Damage Resistant
QR Code has error correction capability. Data can be restored even if the symbol is partially dirty or damaged. A maximum 30% of codewords can be restored. A codeword is a unit that constructs the data area. In the case of QR Code, one codeword is equal to 8 bits.
Readable from any direction in 360°
QR Code is capable of 360 degree (omni-directional), high speed reading. QR Code accomplishes this task through position detection patterns located at the three corners of the symbol. These position detection patterns guarantee stable high-speed reading, circumventing the negative effects of background interference.
Structured Append Feature
QR Code can be divided into multiple data areas. Conversely, information stored in multiple QR Code symbols can be reconstructed as single data symbols. One data symbol can be divided into up to 16 symbols, allowing printing in a narrow area.
QR Code Size Decision Factor
The size of QR Code is decided by determining a symbol version, based on data capacity, character type and error correction level, and by setting a module size, based on the performance of the printer for printing or the scanner for reading.
Securing Margin
When the symbol version and module size are determined, the size of the QR Code symbol is determined. The QR Code symbol area requires a margin or “quiet zone” around it to be used. The margin is a clear area around a symbol where nothing is printed. QR Code requires a four-module wide margin at all sides of a symbol

