How R2-D2 Got Its Name

How did R2-D2 get its name? SlashFilm has the answer:

Rumor has it that George Lucas and a co-worker were editing American Graffiti, when a co-worker asked Lucas for “Reel Two, Dialog Two”, which is abbreviated “R2D2”. Lucas supposedly wrote down the abbreviation and used it as the name of the now famous droid in Star Wars.

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