R2-D2 & See Threepio
One of the most special friendships, well, from a droid perspective, is the friendship between R2-D2 and See Threepio. R2-D2 (Artoo-Detoo), was an astromech droid and undoubtedly the most famous unit of the R2 series. A longtime friend and counterpart of the protocol droid C-3PO, he served the Skywalker family faithfully for many years. Resourceful and spunky, the droid developed an adventurous personality during his many decades of operation.
C-3PO (See-Threepio), was a protocol droida droid specifically designed to interact with organics. He was fluent in over six million forms of communication, and developed a fussy and worry-prone personality throughout his many decades of operation. After being destroyed and discarded on the planet Tatooine before 32 BBY, C-3PO was rebuilt; his salvaged nature gave him special qualities that distinguished him from similar droid models. 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. C-3PO considered various droids and organics to be friends of his, and was very dedicated to them, as well as to any master that he served.