system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] What's with the "Roger, Roger" that the droids say?

Is it supposed to be a joke, like in Airplane?
gpt
We don't have an in-universe etymology for it, but real world; "Roger" used to be used for the phonetic for "R" (it's now Romeo), with "R" being shorthand for "Received and understood".

It's just them announcing that they've received their orders.