PC/104 is an embedded computer standard controlled by the PC/104 Consortium and defines both physical dimensions and computer bus. PC/104 is intended for specialized embedded computing environments where applications depend on reliable data acquisition in an often extreme environment.

The PC/104 form factor has no backplane, and instead allows modules to stack together like building blocks. The stacking of buses is naturally more rugged than typical PCs. This is a result of mounting-holes in the corner of each module which allow the boards to be fastened to each other with standoffs.