What does distance climbed mean on workout machines?

[flamed12]

Just as the title really.

Bit confused as my distance climbed can vary a lot and doesn’t seem to correspond to the time I spend on the machine.

Are you on a treadmill? They can be set to an incline so you are running "uphill", the distance climbed reflects how much elevation there would be if you were running on a real hill. I imagine on step machines there might be something similar.