Operation is a battery-operated game of physical skill that tests players' eye-hand coordination and fine motor skills. The game's prototype was invented in 1964 by John Spinello, a University of Illinois industrial design student at the time, who sold his rights to the game to renowned toy designer Marvin Glass for a sum of US$500 and the promise of a job upon graduation (a promise that was not upheld). Initially produced by Milton Bradley in 1965, Operation is currently made by Hasbro, with an estimated franchise worth of US$40 million. The game is a variant of the old-fashioned electrified wire loop game popular at funfairs. It consists of an "operating table", lithographed with a comic likeness of a patient (nicknamed "Cavity Sam") with a large red lightbulb for his nose. On the surface are several openings, which reveal cavities filled with fictional and humorously named ailments made of plastic. The general gameplay requires players to remove these plastic ailments with a pair of tweezers without touching the edge of the cavity opening. Gameplay Operation includes two sets of cards, "Doctor" and "Specialist." The Specialist cards are dealt out evenly amongst the players at the start of the game, and any extra cards are removed from play. The Doctor cards are shuffled to form a deck and placed face-down. In the US and Australian versions, players take turns drawing the top Doctor card from the deck, offering a cash payment for removing a particular ailment. The player in control uses a pair of tweezers (dubbed "Electro Probe" in earlier versions), connected to the board by a wire, to remove the piece without touching the metal edges of the cavity in which it rests. Successfully doing so awards the value on the card, while a failure gives the player holding the Specialist card for that ailment (if any) a chance to remove it for double value. If the Specialist card holder also fails, or if no player is holding it, the Doctor card is returned to the bottom of the deck. Cards of both types are put out of play as their aliments are removed. If a player draws a particular Doctor card while holding the corresponding Specialist card, he/she may deliberately fail the first attempt in order to have a second chance for double value. The winner is the player with the most money after all ailments have been removed. The