Computer Hardware Terms, Glossary and Dictionary
The external bus, also known as expasion bus, is made up of the electronic pathways that connect the different external devices, such as monitor, printer etc, to the computer. These external devices connect to ports on the back of the computer. Those ports are actually part of a small circuit board or 'card' that fits into a connector on your motherboard inside the case. The connector is called an expansion slot. Traditionally, PCs have utilized an expansion bus called the ISA bus. All new PCs have a PCI bus for performance as well as an ISA bus for backward compatibility.