Usually refers to a decoded or decoding barcode scanner. In the old days, scanners transmitted data called raw count data which is simply a list of the amounts of time spent on each bar and space in a barcode. It was then up to another device called a reader or decoder to translate the raw count data into something meaningful such as ASCII data. The decoder would then transmit the data to a host computer. Today, scanners can decode the raw count data into ASCII or Keycode data and transmit it straight to the host computer.