system
Given the following post, respond as if you're commenting on Reddit:
human
[R1/Star Wars/ESB] What purpose do these big ass glass screens with huge over lapping circles and lines on them serve?
gpt
It's a way of representing 3D space on a 2D surface. 

For example, you put your planet at the center of the glass. You then draw concentric circles around your planet to show distance. The closer the ship is, the closer it moves on the circles. 

*But* this only shows you the distance of the ship, not the approaching vector. So you know the ship is 10,000 kilometres away, but is it heading towards the North Pole, the South Pole or the Equator?

So you draw a line to show the Z axis in oder to get the exact co-ordinates of the ship. If the line comes from the top, it's heading towards the North Pole, if it's heading left to right it's coming from the West, etc.