C-3PO is a protocol droid designed to serve humans, and boasts that he is fluent "in over six million forms of communication." C-3PO is generally seen with his long-time counterpart, R2-D2, a small, quirky astromech droid. Threepio's main function as a protocol droid is to assist with etiquette, customs, and translation so that meetings of different cultures run smoothly. In his time, C-3PO loyally served over forty masters. He hated adventure and space travel, as they often resulted in him coming out on the wrong end of a fight, losing parts, and having them reattached, sometimes incorrectly. Together with his fellow droid R2, Threepio played a vital and pivotal role in the Galaxy's history, however lowly he thought of himself.
Star Wars movies C-3PO appeared in.