I am completely oblivious to all terms in all facts of life (you would be surprised at how I do in my honors geometry class when I call shapes such as trapezoids 'parallel median base quadrilaterals' and isosceles triangles 'bicongruent triple angular entities') but I can somewhat explain how calc to calc transfer works in a way.
Calc to calc is actually a pretty simple process -- as far as I know, a cable sends pure, raw data in 8 bit form across the wire. The thing is, this can prove to create bad transfers, because if the two calcs are not synced up at the same frequency (again, IDK the term) then you might only transfer half the data correctly. But, depending on how you detect byte sending, you might make the calculator wait until it receives a non zero (or sometimes a non -1) from the opposite end. And, when it does receive it, it might send back a value such as 1 to the output machine to say 'I got it already!' and then output machine will then proceed to the next 8 bit value until it's all done.
USB, however, I believe that is a whole different story. I don't plan on explaining it or even learning about it, I've heard it's extremely complex.