A barcode is an optical machine-readable representation of data. It is made up of bars and spaces that vary in size. While barcodes are used in the real world, barcodes are also found on the Game Grid (in the cockpit of Flynn's Recognizer) and in Space Paranoids Online.
Space Paranoids Online[]
In 1982, Kevin Flynn secretly put barcodes in his video game Space Paranoids. The codes, when entered into Flynn's work server, revealed Flynn's plans and sketches of his TRON system.