"Yep, Spike's a pretty useful guy," she said with a grin.

"So... if the words are in one of these things --" She tapped her work console. "Then I should think of it like paper, and if it's supposed to go somewhere else, then the machines do the work of a mailpony and send it to where it's supposed to go?" Putting a hoof to her chin, she turned that around in her head till it made some sort of sense. "Okay, I can get that! So I guess these 'radio' waves are like a pegasus, they fly through the air, and if it goes through 'cables' it's like an earth pony carrying them on the ground?"

No one could call Rainbow Dash stupid. Of course, if you call her an egghead or a book-lover she might get angry...