System Unit

Serial Port
A port, or interface, that can be used for serial communication, in which only 1 bit is transmitted at a time. Most serial ports on personal computers conform to the RS-232C or RS-422 standards. A serial port is a general-purpose interface that can be used for almost any type of device, including modems, mice, and printers (although most printers are connected to a paralle port).

Parallel Port
A parallel interface for connecting an external device such as a printer. Most personal computers have both a parallel port and at least one serial port. On PCs, the parallel port uses a 25-pin connector (type DB-25) and is used to connect printers, computers and other devices that need relatively high bandwidth. It is often called a Centronics interface after the company that designed the original standard for parallel communication between a computer and printer. (The modern parallel interface is based on a design by Epson.)

Universal Serial Bus
A computer interface with a maximum bandwidth of 1.5 Megabytes per second used for connecting computer peripherals such as printers, keyboards and scanners.

Firewire Port
Firewire ports are forms of a serial port that make use of FireWire technology to transfer data rapidly from one electronic device to another. The FireWire port has been in common use since 1995, when Apple, Inc. first began to include the port on a number of digital camcorders. Today, the FireWire port is used on a number of other devices. A FireWire port can reach up to 400 Mbps, the data transfer is relatively fast and also results in excellent quality.

Expansion Card

An integrated circuit card that plugs into an expansion slot on a motherboard to provide access to additional peripherals or features not built into the motherboard. Also known as an add-on card, internal card or interface adapter, an expansion card is an electronic board or card added in a desktop computer or other non-portable computer to give that computer a new ability, such as the ability to connect to another computer using a network cable. Below is a list of expansion cards that could be installed in a an available expansion slot.

Network Interface Card (NIC)

A network interface card is used to connect a computer to an Ethernet network. The card (shown in the figure below) provides an interface to the media. This may be either using an external transceiver (as shown) or through an internal integrated transceiver mounted on the network interface card PCB. The card usually also contains the protocol control firmware and Ethernet Controller needed to support the Medium Access Control (MAC) data link protocol used by Ethernet.


Plug and Play

Plug and Play technology provides a combination of software and hardware support that enables the Windows operating system to detect and configure hardware with little or no user involvement. It framework defines several base components that can be implemented in any environment. Buses, devices, and resources are abstracted from the base components via hardware-specific enumerators, arbitrators, and device drivers. This ensures that the framework is extensible not only to other environments but to future bus and device architectures.

Sockets

A server application normally listens to a specific port waiting for connection requests from a client. When a connection request arrives, the client and the server establish a dedicated connection over which they can communicate. During the connection process, the client is assigned a local port number, and binds a socket to it. The client talks to the server by writing to the socket and gets information from the server by reading from it. Similarly, the server gets a new local port number (it needs a new port number so that it can continue to listen for connection requests on the original port). The server also binds a socket to its local port and communicates with the client by reading from and writing to it.

Chips

Chip" is short for microchip, the incredibly complex yet tiny modules that store computer memory or provide logic circuitry for microprocessors. Perhaps the best known chips are the Pentium microprocessors from Intel. The PowerPC microprocessor, developed by Apple, Motorola, and IBM, is used in Macintosh personal computers and some workstations. AMD and Cyrix also make popular microprocessor chips.
Slots

Buslines

It is a line for bus to transfers data between computer components inside a computer or between computers.