HueCode is a proprietary code developed by Robot Design Associates. The code is made up of blocks of cells containing more than one bit per cell. This is done by using shades of gray or color. The symbol can be printed on plastic or paper. Information densities vary according to the specific techniques used, but range between under 640 Bytes/sq. in. using laser printers to over 40,000 Bytes/sq. in. using dye sublimation printers. HueCode is read using a flatbed scanner set to 400x400 DPI and proprietary software. The code is intended to store text information on the backs of business cards or medical cards.