In all the Star Wars movies, R2D2 just boops and beeps his way around. And everyone understands him perfectly, though he is obviously not speaking Basic.
How do people understand him - is there like an astromech language? If so, then would one have to learn it, or is it comprised of feelings and emotions (expressed in beeps), essentially making a tonal language?
If I may be permitted to use an example from the prequels without too many lynch mobs forming, Anakin Skywalker converses frequently with Artoo while in the Naboo fighter, but he couldn't have had much schooling at the age of eleven, especially because he was a slave.
So how would people, Anakin especially, be able to understand astromechs?