Order 66 Cody

CC-2224, or Commander Cody, receiving Order 66 at the end of the Clone Wars

Clone Protocol 66, better known as Order 66, was a clone contingency order that ordered all Clone Troopers within the Galactic Republic's military to turn on their Jedi Generals, as they were seen as traitors to the Republic, and later Empire. The Order was implanted into the Clones by Darth Sidious, or Sheev Palpatine, as a way for him to eliminate the Jedi Order and for him to establish the Galactic Empire, along with his Stormtrooper military.