what are FID pads for

[avion]

robertferanec There are 4 round pads on the pcb, 2 on top and 2 on bottom. They dont connect to anything else, no nets. The pads are named FID, what are there used for?

[robertferanec]

These are called fiducials and they are used during Assembly process (the assembly machine use them as reference points to know where to place components). Usually we place some on PCB and some on PCB panel (you would like to have at least three fiducials in corners of the PCB or PCB panel).