QR Code is registered trademark of DENSO WAVE INCORPORATED. This registered trademark applies only for the word "QR Code", and not for the QR Code pattern (image).
A QR code (abbreviated from Quick Response code) is a type of matrix bar-code (or two-dimensional code) first designed for the automotive industry. More recently, the system has become popular outside of the automotive industry due to its fast readability and comparatively large storage capacity. The code consists of black modules arranged in a square pattern on a white background. The information encoded can be made up of any kind of data (e.g., binary, alphanumeric, or Kanji symbols).
The amount of data that can be stored in the QR code depends on the character set, version and error correction level. The maximum values for version 40 with error correction capacity levels L, M, Q and H are: