The NXT for FRC works, but depending on your audience, here is a bit more.
cRIO stands for compact Reconfigurable Input Output and is pronounced see-ree-oh. It is categorized as a Programmable Automation Controller or PAC. In FRC, it executes the team robot code, controls the output signals, monitors the input signals, and implements the safety protocol.
These articles describe how it is used when not bolted to FRC robots.
Greg McKaskle