A protocol droid assists its owner in communicating, mainly with the translation of languages in the Star Wars universe and in correctly observing the norms and etiquette of unfamiliar cultures and civilizations. Protocol droids can alternatively be used primarily as a mobile data processing system. Because they are frequently called upon to accurately replicate various rituals and forms of polite address, they usually have a humanoid body shape that allows them to supplement their speech with appropriate gestures and posture, as opposed to the more utilitarian, non-anthropomorphic design of other droids.

Probably because a protocol droid is a familiar sight in the circles of the wealthy, diplomatically or governmentally important and other common targets for their services, some assassin droids, like HK-47, masquerade as protocol droids to avoid attention and get close to their targets.

The 3PO-series protocol droid was a Human-cyborg relations protocol droid produced by Cybot Galactica. They were very similar to the TC-series, 3PX-series, and 5YQ-series protocol droids.

Manufactured by Cybot Galactica on the factory world of Affa, the 3PO-series protocol units were considered the most advanced Human-cyborg relations droids in the market for over a hundred years. Production on the line began at least as far back as 112 BBY and continued well into the New Republic era.

The success of the 3PO-series led Cybot Galactica to produce the C-series protocol droids during the rule of the New Republic. They had a market cost of 3,000 credits.

The typical 3PO-series droid stood at approximately 1.7 meters in height with a humanoid build. Most units were programmed with a subservient, service oriented personality and a typical 3PO unit would never attack, under any circumstances even if it was in self-defense.

Each droid was equipped with a SyntheTech AA-1 VerboBrain making them capable of storing enormous amounts of information, the additional memory space was often used to keep communication modules in the active memory so that long delays could be avoided while searching for linguistic information on mid-translation. A TranLang III Communications module allowed them to be fluent in over six million forms of communication, even if they could not respond in all of them for a lack of proper communication appendages. They also had the skills necessary to quickly analyze new unregistered languages and translating them into more well-known ones.

They were even provided with an olfactory sensor that allowed them to comprehend pheromonal communication. Other useful features were a factory-standard restraining bolt mount, and a the fact that their shutdown switch was conveniently located at the back of his neck, on a very easy to reach place.

Some models, such as the pricey E-3POs, also included the TechSpan I module, making it possible to interface with Imperial networks and undocumented technologies of Imperial subcontractors.

Droids in the 3PO-series came in a variety of colors, although their colored plating was known to be prone to corrosion:

* Gold
* Silver
* White
* Red
* Black
* Jade
* Blue
* Blue and gold
* Green
* Purple

It is very likely that there were more colors and color combinations.

STATS:
3PO Series Protocol Droid CL: 0
Medium droid (3rd-degree) nonheroic 1
Init: -1 Senses: Perception +1
Languages: Basic, Binary, 3 unassigned
Defense: Ref: 9 Fort: 9 Will: 11
HP: 2 Threshold: 9
Immunity: droid traits
Speed: 6 squares (walking)
Melee: unarmed -1 (1d3-1)
Fighting Space: 1 square Reach: 1 square
Base Atk: +0 Grp.: -1
Abilities: Str: 8 Dex: 9 Con: - Int: 12 Wis: 13 Cha: 15
Feats: Linguist, Skill Focus (Persuasion), Skill Training (Knowledge [bureaucracy]), Skill Training (Knowledge [galactic lore])
Skills: Knowledge (bureaucracy) +6, Knowledge (galactic lore) +6, Knowledge (social sciences) +6, Persuasion +12
Systems: walking locomotion, basic processor, translator unit (DC 5), 2 hand appendages, vocabulator
Possessions: audio recorder
Availability: Licensed Cost: 3,000 credits