system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do directions work in space?
gpt
They're either relative to the orbit that the ship is on(prograde, retrograde, normal, anti-normal, radial in, radial out) or relative to a fixed set of reference points(Earth, moon, or sun) which you can then use up/down or north/south, east/west to refer to directions.

Once you have your reference set you can define things with angles just like we do here on Earth with incilination(up/down) and ascension(left/right rotation)