Communication between computer and ROV


I am building the OpenROV 2.8 with the kit this summer with the interest of modifying and adding to it. I was curious how the information from the computer and controller to the ROV communicated and interacted with electronics ex. Servos. I am a bit stumped considering I will need to know how this works in order to modify.
Thank you!!
Also, is it alright to connect the beagle board to a moniter and look around on it?