What is the docking screen supposed to show?

[Galvax]

I've been playing KSP for a couple months now and have progressed to docking multiple ships together to create space stations. I watched several different tutorials on youtube to learn how to reliably dock. However, I've noticed that no one uses the docking mode. I have tried using it, but I'm confused as to what it's supposed to do other than alternate between translational and radial directional keys. Nothing shows up on the little window when I click the docking mode button. I see the crosshairs that shift around as I adjust my trajectory, but what am I supposed to line it up with? If someone has a link to a video that explains the ingame docking mode, I'd appreciate seeing it.

[Stamp20]

All docking mode really does is allow you to use WASDQE for translation instead or rotation. If you're good with the normal translation keys, it's unnecessary.

The square with the orange crosshair is the pitch/yaw/roll bars in the staging screen, but for translation instead.

[Geonovast]

The only use I've ever gotten out of the docking mode was being able to switch joystick configs for planes and rockets.

For planes, I would use forward/back on the joystick for pitch, left/right for roll, and twisting the stick for yaw.

On a rocket, that doesn't make a whole lot of sense, so I swap the roll/yaw.  You can do that with the docking mode quickly since they can be configured separately. Planes flown in normal mode, rockets flown in docking mode.

[XLjedi]

A shame that tab doesn't do something useful, like show an alignment indicator, or distance to target.  Those are really the only two docking bits of info that are missing from stock for some very odd reason.  If I had those, I'd be able to dock from orbit view in stock.

Edited March 14, 2020 by XLjedi