C-3PO (See-Threepio) was a 3PO-series protocol droid designed to interact with organics, programmed primarily for etiquette and protocol. Sometimes referred to as Threepio, he was fluent in over six million forms of communication, and developed a fussy and worry-prone personality throughout his many decades of operation. Along with his counterpart, the astromech droid R2-D2, C-3PO constantly found himself directly involved in pivotal moments of galactic history, and aided in saving the galaxy on many occasions.