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.
C-3PO's main function as a protocol droid is to assist with etiquette, customs, and translation so that meetings of different cultures run smoothly. Together with his fellow droid R2-D2, C-3PO played a vital and pivotal role in the Galaxy's history. - - From Wikipedia, the Free Encyclopedia
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