Nikon Lens: A (Auto-focus) vs. A/M (Auto-focus/Manual)

Question

I have two lenses which are 18-140 VR and 50 1.8G. On the 18-140 VR I got a button showing A and M while on the 50 1.8 I got a button showing A/M and M. I understand that A is for auto-focus and M is for manual.

My question is, is there any difference between a just A and A/M option. For instance does overriding the focus on the 18-140 VR lens cause any damage to the lens as it is just A while the same would be fine with the 50 1.8G which is A/M?

Answer 1

The 50 1.8G has the full-time manual focus override feature which means you can manually focus while in A/M Autofocus mode.

The 18-140 VR also has the full-time manual focus override feature even though it ony has A and M on the switch.

Some lenses have a more basic type of autofocus and must be switched to Manual mode before manually focusing.