- "I'm not much more than an interpreter, and not very good at telling stories."
Protocol droids were programmed mostly for etiquette and were often used as translators between sentients or between sentients and computers. They were generally designed to look like the sentients they would be serving; for example, 3PO-series protocol droids were humanoid.
They possessed knowledge about various cultures and customs, both to advise those for whom they were working and to ensure their own behavior was diplomatic and culturally sensitive.
Protocol droids constructed around 4000 BBY (around the time of the Great Sith War and the Jedi Civil War) were frequently engineered with certain situational and behavioral shifts set to occur whenever another design-generation was reached. A number of these droids underwent radical changes with each new generation—for example when a C7-model droid supplanted the C6 variety. Each numeric "jump" in sequence could have had wide-ranging changes in functionality and temperament during that historical period.
Cybot Galactica, the most famous and successful manufacturer of protocol droids, outfitted them with SyntheTech AA-1 VerboBrains to give their droids personalities with emotions and the ability to learn and grow very similar to organic beings. The 3PO unit possessed a TranLang III communications module that could reproduce over six million languages, as well as reproduce any sound it picked up. Linguistic modules were also used to improve their speech functions. 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.
There were very few feminine-programmed protocol droids.
- Jedi Academy
- Jedi Academy: Return of the Padawan
- Jedi Academy: The Phantom Bully
- LEGO Star Wars: The Video Game
- LEGO Star Wars: The Complete Saga
- LEGO Star Wars: The Quest for R2-D2 film
- LEGO Star Wars II: The Original Trilogy
- LEGO Star Wars: Bombad Bounty
- LEGO Star Wars: The Han Solo Affair
- LEGO Star Wars: The Padawan Menace
- "Fortune, Fate, and the Natural History of the Sarlacc" — Star Wars Tales 6