I have had an Anet 3d printer for a few months now and have made steady progress learning with pla how to get a good consistent print.

I have seen many 'kit’s to add auto levelling capability.

My question is: how do these work ?..

So they just sense the height of the bed in one corner and ‘assume’ that the other corners are the same height ?..or do they sense the height in the 4 corners and adjust the gcode accordingly to compensate for a bed that may not be level ?

Any thoughts appreciated

Simon