QR Code is a two-dimensional barcode that is readable by smartphone. It allows to encode over 4000 character in a two dimensional barcode. QR Codes may be used to display text to the user, to open a URL, Save a contact to the address book or to compose text message. "QR Code" is a registered trademark of DENSO WAVE INCORPORATION.
To read QR Codes with a smartphone, you can just use the default camera app.
On desktop devices, you can just bookmark the Scan section of (QR Code Ganeratore Website) Than can be useful to send a link from a phone to your desktop browser for example.