system unit

expansion card:
A system unit, also known as a base unit, is the main body of a desktop computer, typically consisting of a plastic enclosure containing the motherboard, power supply, cooling fans, internal disk drives, and the memory modules and expansion cards that are plugged into the motherboard, such as video and network cards.This is the technical term that refers to the box that houses your computer. The system unit refers to the computer itself but does not include the monitor, the keyboard, the mouse, or any other peripherals. I suppose most people will probably know what you mean when you refer to "the box," but saying "system unit" will definitely make you sound more sophisticated.

network interface card:

A network interface controller (NIC) is a hardware device that handles an interface to a computer network and allows a network-capable device to access that network. The NIC has a ROM chip that contains a unique number, the multiple access control (MAC) Address that is permanent. Sometimes the words 'controller' and 'card' are used interchangeably when talking about networking because the most common NIC is the network interface card. Although 'card' is more commonly used, it is less encompassing. The 'controller' may take the form of a network card that is installed inside a computer, or it may refer to an embedded component as part of a computer motherboard, a router, expansion card, printer interface or a USB device.

cache memory:

A CPU cache is a cache used by the central processing unit of a computer to reduce the average time to access memory. The cache is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations. As long as most memory accesses are cached memory locations, the average latency of memory accesses will be closer to the cache latency than to the latency of main memory.When the processor needs to read from or write to a location in main memory, it first checks whether a copy of that data is in the cache. If so, the processor immediately reads from or writes to the cache, which is much faster than reading from or writing to main memory.

plug and play:

Plug and Play is a set of networking protocols promulgated by the UPnP Forum. The goals of UPnP are to allow devices to connect seamlessly and to simplify the implementation of networks in the home data sharing, communications, and entertainment and in corporate environments for simplified installation of computer components. UPnP devices are "plug-and-play" in that when connected to a network they automatically announce their network address and supported device and services types, enabling clients that recognize those types to immediately begin using the device.

sockets:

Internet sockets are an application programming interface application program . usually provided by the operating system. Internet sockets constitute a mechanism for delivering incoming data packets to the appropriate application process or thread, based on a combination of local and remote IP addresses and port numbers. Each socket is mapped by the operational system to a communicating application process or thread.

chips:In computing, the term chipset is commonly used to refer to a set of specialized chips on a computer's motherboard or an expansion card. In personal computers the first chipset for the IBM PC AT was the NEAT chipset by Chips and Technologies for the Intel 80286 CPU. The northbridge links the CPU to very high-speed devices, especially main memory and graphiccs .controllers, and the southbridge connects to lower-speed peripheral buses (such as PCI or ISA).

slots:

An opening in a computer where you can insert a printed circuit board. Slots are often called expansion slots because they allow you to expand the capabilities of a computer. The boards you insert in expansion slots are called expansion boards or add-on boards.
Do not confuse slots with bays. Bays are sites within the computer where you can install disk drives. Typically, slots are in the back of the computer and bays are in the front.

business:

A Businesses are predominant in capitalist economies, most being privately owned and formed to earn profit that will increase the wealth of its owners and grow the business itself. The owners and operators of a business have as one of their main objectives the receipt or generation of a financial return in exchange for work and acceptance of risk. Notable exceptions include cooperative enterprises and state-owned enterprises. . The distinction between these institutions and a business is that socialist institutions often have alternative or additional goals aside from maximizing or turning a profit. service port:Personal computers have various types of ports. Internally, there are several ports for connecting disk drives, display screens, and keyboards. Externally, personal computers have ports for connecting modems, printers, mice, and other peripheral devices.
Almost all personal computers come with a serial RS-232C port or RS-422 port for connecting a modem or mouse and a parallel port for connecting a printer. On PCs, the parallel port is a Centronics interface that uses a 25-pin connector. SCSI (Small Computer System Interface) ports support higher transmission speeds than do conventional ports and enable you to attach up to seven devices to the same 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.)
A newer type of parallel port, which supports the same connectors as the Centronics interface. Both of these parallel ports support bi-directional communication and transfer rates ten times as fast as the Centronics port.

universal serial bus:

USB (Universal Serial Bus) is a way of setting up communication between a computer and peripheral devices. USB is intended to replace many varieties of serial and parallel ports. USB can connect computer peripherals such as mice, keyboards, PDAs, gamepads and joysticks, scanners, digital cameras, printers, personal media players, flash drives, and external hardrives. For many of those devices, USB has become the standard connection method. USB was designed for personal computers, but it has become commonplace on other devices such as PDAs and video game consoles, and as a power cord between a device and an AC adapter plugged into a wall plug for charging.

firewire port:

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.