C-3PO and R2-D2 are two iconic DROIDS from the Star Wars universe. They are both classified as ANDROIDS, which are robots designed to look and act like humans. C-3PO is a protocol droid, meaning he is programmed to assist with diplomatic and etiquette-related tasks, while R2-D2 is an astromech droid, meaning he is programmed to assist with space travel and repairs. Together, they have been on many adventures and have become beloved characters in the Star Wars franchise.