(1) (
Input/
Output port) An I/O port is a socket on a computer that a cable is plugged into. The port connects the CPU to a peripheral device via a hardware interface or to the network via a network interface. See
port,
standards - hardware interfaces,
DisplayPort,
HDMI and
USB.
(2) (
Input/
Output port) In a PC, an I/O port is an address used to transfer data. See
PC I/O addressing.