QR Code
QR codes transmit information by graphic code of black and white pixels. The QR code is two-dimensional. This means that information is transmitted by reading both the horizontal and vertical positions of the pixels rather than just the horizontal position.
QR codes can be decoded with smart phone and QR scanner devices. This allows web addresses to be encoded in QR codes, which can automatically send the scanning device to the URL specified in the default browser. The best use of QR code is WhatsApp. It is used to use the WhatsApp application on the computer.
The most visually obvious element of the QR code are the square blocks used to guide the code when scanned by the reader. This allows the code to be scanned in any direction, including upside down, and convey the correct message. It appears as a total of four blocks, three of which are embedded in the corners and one in the lower right.
The version format, error checking version and decoding mask are coded around these blocks. The QR code is surrounded by a white area called the "silent zone" that helps the reader find the edges of the code.
QR codes can be of various sizes. The largest QR code, 177 x 177, contains up to 1,264 characters of ASCII text. The most commonly used QR size is between 29 x 29 and 33 x 33, which can hold around 50 ASCII characters. All sizes can work together with modern reading devices such as smartphones.