ShotCodes are circular barcodes, originaly created by High Energy Magic of Cambridge University. They are dartboard-like circles, with a bulls eye in the centre and datacircles surrounding it.
Technology
A shotcode consists of datacircles surrounding a center point. A shotcodes reader reads databits from these datacircles by measuring the angle and distance from the bulls eye for each.
ShotCodes can be read with a regular camera (including those found on mobile phones and webcams) without need to buy other hardware. ShotCodes are different from regular barcodes. The main difference is that they do not store regular data, but they store a look up number consisting of 49 bits of data. This design needs a central server which holds information regarding what url maps with the scanned shotcode number. The url is send back to the scanner, and the user can be redirected to the right url.
