A port is considered a connection point that acts as an interface between the machine and external devices such as mouse, printer, modem etc. Ports come in two forms−
Internal port − The motherboard attaches to internal devices such as hard disk drive, CD drive, internal modem, etc.
External port − The motherboard links to external devices such as router, keyboard, scanner, flash drives, etc.
Serial ports relay data one bit at a time, sequentially. And they do require one wire to transmit 8 bits. And it allows them slower as well. Serial ports typically consist of male 9-pin or 25-pin connectors. These are often referred to as COM (communication) ports, or RS323C.
Parallel ports can accept or transmit 8 bits or 1 byte at a time. In the form of 25-pin female pins, parallel ports are used to link printers , scanners, external hard disk drives, etc.
USB stands for Serial Universal Bus. This is the industry norm for digital data connection over short distance. USB port is a normal port for connecting a range of devices such as a computer, camera, keyboard, speaker, etc.
PS/2 stands for Personal System/2. It is a regular 6-pin female port that attaches to the male mini-DIN tube. IBM implemented PS/2 for attaching the mouse and keyboard to personal computers. This port is now mostly obsolete, but some IBM-compatible systems that have the port.
Infrared port is a network allowing data to be exchanged wirelessly within a 10 m range. Two devices which have infrarot ports are positioned facing each other such that infrarot light beams can be used for information sharing.
Bluetooth is a telecommunication standard that enables wireless connectivity over short range wireless link between phones , computers, and other digital devices. Bluetooth port enables Bluetooth-enabled devices to synchronise. Bluetooth ports are of two types –
FireWire is the standard interface for Apple Computer to allow high speed communication through serial bus. It's also called IEEE 1394 and is primarily used by audio and video applications such as optical camcorders.