Bus

A bus is a hardware channel for communication between multiple devices. Also often called a system bus or hardware bus. When it's a channel between only two devices it usually is called a port instead.

Disks/drives

 * IDE
 * SATA
 * SCSI/SAS

Extension slots

 * ISA/EISA
 * PCI
 * PCI Express
 * VESA local bus

Universal/plugin

 * PCMCIA
 * IEEE 1394 also known as FireWire
 * USB

Misc.

 * AGP
 * Front Side Bus