Note: See the header of this page for links for related articles “how to make a QR code” and “how to scan a QR code.”
Although initially used for tracking parts in vehicle manufacturing, QR codes now are used in a much broader context, including both commercial tracking applications and convenience-oriented applications aimed at mobile phone users (termed mobile tagging). QR codes may be used to display text to the user, to add a vCard contact to the user’s device, to open a Uniform Resource Identifier (URI), or to compose an e-mail or text message. Users can generate and print their own QR codes for others to scan and use by visiting one of several paid and free QR code generating sites or apps.
QR codes storing addresses and Uniform Resource Locators (URLs) may appear in magazines, on signs, buses, business cards, or almost any object about which users might need information. Users with a camera phone equipped with the correct reader application can scan the image of the QR code to display text, contact information, connect to a wireless network, or open a web page in the telephone’s browser. This act of linking from physical world objects is termed hardlinking or object hyperlinking.
The browser supports URI redirection, which allows QR codes to send metadata to existing applications on the device. In the Apple iOS, a QR code reader is not natively included, but more than fifty paid and free apps are available with reader and metadata browser URI redirection ability.