A resourceful astromech droid, R2-D2 served Padmé Amidala, Anakin Skywalker and Luke Skywalker in turn, showing great bravery in rescuing his masters and their friends from many perils. A skilled starship mechanic and fighter pilot's assistant, he formed an unlikely but enduring friendship with the fussy protocol droid C-3PO.
C-3PO is a droid programmed for etiquette and protocol, built by the heroic Jedi Anakin Skywalker, and a constant companion to astromech R2-D2. Over the years, he was involved in some of the galaxy’s most defining moments and thrilling battles -- and is fluent in more than seven million forms of communication. In the years after the Empire's defeat, C-3PO acquired a red-plated arm, keeping the mismatched limb to honor a fellow droid's sacrifice.
Podracing is extremely dangerous, as is maintaining the speedy vehicles. In the hectic pace of a race, safety comes in second place to winning. As such, the cheap and expendable pit droids often bolt out onto the racetrack to repair still cycling superheated engines with no regard to their personal safety. When not in use, pit droids fold up into a compact package. They spring to activation when needed. A tap on the nose signals the droid to collapse back into stowed mode and rest.