In the industrial world, two bus architectures are quite fashionable currently: PC/104 and PC/104+. Both are standard in PC-class single-board computers.

Both standards refer to specific form factors for printed circuit boards as well as electrical/mechanical specifications for board interconnections. The practical advantage of these buses is that they allow circuit boards to be stacked vertically using a plug-and-socket kind of connector on one side of the device.

The electrical and logical layout of the two buses is identical to ISA (PC/104) and PCI (PC/104+), so software won’t notice any difference between the usual desktop buses and these two.