A scratchcard (also called a scratch off, scratch ticket, scratcher, scratchum, scratch-it, scratch game, scratch-and-win, instant game, instant lottery, scratchie, lot scrots, or scritchies) is a card designed for competitions, often made of thin cardstock or plastic to conceal PINs, where one or more areas contain concealed information which can be revealed by scratching off an opaque covering. Applications include cards sold for gambling (especially lottery games and quizzes), free-of-charge cards for quizzes, fraudulent free cards encouraging calls to premium rate phone services, and to conceal confidential information such as PINs for telephone calling cards (otherwise known as recharge cards) and other prepaid services. In some cases, the entire scratchable area needs to be scratched to see whether a prize has been won—the card is printed either to be a winner or not—or to reveal the secret code; the result does not depend upon what portions are scratched off. In other cases, some but not all areas have to be scratched; this may apply in a quiz, where the area corresponding to the right answer is scratched, or in some gambling applications where, depending on which areas are scratched, the card wins or loses. In these cases, the card becomes invalid if too many areas are scratched. After losing, one can scratch all areas to see if, how, and what one could have won with this card. Technology The scratchcard itself is made of paper-based card, or plastic, with hidden information such as PIN or HRN (Hidden Recharge Number) printed on it, covered by an opaque substance (usually latex). The original cards were covered with an environmentally unsafe solvent based coating. In the late 1980s, adhesive specialist Jerome Greenfield invented a safe water-based coating still used in scratchers today that can be scratched off relatively easily, while resistant to normal abrasion. Other types of scratch panel are scratch labels, hot stamp foil or 'sandwich' label which are technologies that is easy to produce for manufacturers without specialised equipment for applying latex panels. Unlike silkscreen latex panels that bond with the card body, labels are distinctly separate to the card body and applied by adhesion which makes them prone to sophisticated and fraudulent manipulation. Gambling and quizzes Origins The original game tickets were produced using manual randomization techniques. In 1974 the American company Scientific Games Corporation led by scientist John Koza and retail promotions specialist Daniel Bower produced the first computer-generated