Around 28:20 in the movie, after Ramius' opening speech for Red October's mission and while the crew is singing the Soviet anthem, he gives the numbers 2/5/0 to his navigator to use as a direction.
I've seen this three-numbers system used in a lot of sci-fi and I always brushed it off as technobabble, but this is the first time I've seen it in a historical fiction that aims for technical realism, so I guess these numbers do mean something. And searching with something as vague as "three numbers", "navigation", "direction" and "submarine" isn't precise enough for Google.
Am I right in assuming this three-numbers system is (or was) used in the real world? If so, does it have a specific name and what do the numbers represent?