The course adjustment moves the stage of the microscope further/closer away from the objective lens (it is used for general focusing), and the fine adjustment moves the objective lens very small distances for finer focusing.
fine adjustment knob-permits exact focusing by moving objectives slightly coarse adjustment knob-moves the body tube for the objective to be in correct distance from the object being viewed
The coarse focus adjustment moves the lens (or the stage, depending on the construction of the microscope). So does the fine adjustment but the fine does it much less and much more accurately (less...