Hello

I am developing my own 3d printing software and have trouble with the extruder.
I have read that the gcode g1 command moves to the given position.
but there is also a E paramenter which pulls out the given amount of fillament from begin to end.
But is this function needed?
If yes:why?
Or Can i just make it that the speed of it is set To match the speed of the x and y and z axis.
Or will my 3d prints than be incorrectly printed?

Can anyone help my?


Thanks