In a number of places in the star wars films where we see R2-D2 interface directly with a computer, his interface arm and the socket it plugs into both rotate periodically.

The out-of-universe explanation of this would of course be that it looks cool on film and shows that something is happening, but is there an in-universe explanation?

  • 7
    To expand on the out of universe explanation, the standard images of computers at that time were blinking lights and spinning tape reels. I think they were evoking the latter with R2's spinning.
    – Politank-Z
    Jan 11 '16 at 23:09
  • 33
    Have you ever plugged in a USB device right-side-up on the first try? Jan 11 '16 at 23:09
  • 2
    @RyanVeeder, R2's data interface is round. You don't see it rotating to orient itself before plugging in, it just plugs in then things rotate. Not like a USB port at all.
    – Monty Wild
    Jan 11 '16 at 23:20
  • 1
    Asked and (kinda) answered on Movies:SE - "Is there any real-world “science” behind R2-D2’s computer interfacing arm?"
    – Valorum
    Jan 11 '16 at 23:23
  • 2
    @RyanVeeder usually takes three goes, doesn't it?
    – HorusKol
    Jan 12 '16 at 1:53

These are officially called scomp links. They are the standard data interface for the Star Wars universe.

The only explanation is that computers of the day (in-universe) seem to have quite a few physical components to them. For instance, we see in Rogue One that the Imperial Archives store data on some sort of drive/tape (this is a deleted scene so you can see the device better)

enter image description here

We also see Princess Leia get this information onto a data card and put it into R2D2 in ANH.

It's entirely possible that R2D2 is physically having to read "sectors" of data as the arm spins. Need a different set of data? Rotate the interface (just like a hard drive). As manual as these other data devices are, this would make sense.


all data storage technology of the time rotated in some way. hard drives, floppy disks, tape reels, Zip disk, Jazz drive. it rotated the media to the read head. think of it like an old school record.... for that matter you can throw CD's, records, and even mini disk into the list above. they just came up with a "cooler" look for it.

  • 3
    This would be an out-of-universe explanation. It is not the requested in-universe explanation.
    – Monty Wild
    Aug 22 '16 at 6:58
  • 1
    It is the in-universe explination. All things film related are influenced by real word scenarios. Aug 23 '16 at 16:37
  • Yeah, back in 1977 digital storage of information was not even really a concept yet, in order to access a certain point in memory, you have to move the physical tape with the memory to the read head. R2 does this by spinning the ports with his arm thing. If you want an example of how tape makes a computer work, look up Turing Machines, where there was no CPU chip, just tape rotating in certain ways!
    – Daishozen
    Mar 2 '18 at 0:06

Not the answer you're looking for? Browse other questions tagged or ask your own question.