Droids and computers

Droids and computers used either the natural languages that their masters used, usually Basic, or special machine languages. Protocol droids such as C-3PO were "fluent in over six million forms of communication" and were often employed as translators. Astromech droids such as R2-D2 were able to understand commands in Basic and perhaps other languages, but could only communicate through an information-dense language of beeps and whistles; although devices existed that could translate this language into Basic (such as the display in an X-wing cockpit that allowed the ship's astromech and pilot to commmunicate). Simpler droids communicated only through sounds indicating affirmative/negative, or other simple replies.