System Unit

RAM
Random access memory is also known as RAM. It is a form of computer data storage. It takes the form of integrated circuits that allow stored data to be accessed in any order with a worst case performance of constant time.

Cache
Cache is a component that transparently keeps data so that if in the future the data is wanted, it can be served faster. The data that is stored within a cache might be values that have been computed earlier or duplicates of original values that are stored elsewhere. If the wanted data is containted in the cache (cache hit), this request can be served by reading the cache, which is more faster.

ROM

Read-only memory is also known as ROM is a category of storage medium used in computers and other electronic devices. The data in ROM cannot be changed or can be changed but in a very difficult way. Therefore, it is mainly used to distribute firmware. 

Flash Memory

Flash memory is a non-volatile computer storage chip that can be electrically erased and reprogrammed. It is basically used in memory cards, USB, MP3 player and solid-state drives for general storage and transfer of data between computers and other digital products. 

Graphic Card

Graphics card is an expansion card whose affair is to accomplish output images to a display. Most video cards offer added functions, such as accelerated rendering of 3D scenes and 2D graphics, video capture, TV-tuner adapter, MPEG-2/MPEG-4 decoding, FireWire, light pen, TV output, or the ability to connect multiple monitors (multi-monitor).

Sound Card

Sound card is also known as audio card is an inside computer expansion card that furthers the input and output of audio signals to and from computer under control of computer programs. The word sound card is also related to external audio interfaces to generate sounds as opposed to using hardware inside the PC.

Network Interface Card

Network interface card is an abstract as NIC. It is an expansion board that inserts into a computer so that the computer can be connected to a network. Most NICs are build for a certain type of network, protocol, and media, although some can serve multiple networks.

Plug and Play

Plug and play is a term used to describe the characteristic of a computer bus, or device specification, which facilitates the discovery of a hardware component in a system, without the need for physical device configuration, or user intervention in resolving resource conflicts.

Universal Serial Bus(USB)

Universal serial bus(USB) is designed to authorize communication between devices and a host controller, which has effectively changed a variety of previous interfaces such as serial and parallel ports. USB was designed for personal computers, but it has become commonplace on other devices such as smartphones, PDAs and video game consoles, and as a power cord.

Serial Port

Serial port is a serial communication physical interface through which information transfer in or out one little at a time. Throughout most of the history of personal computers, data transfer through serial ports connected the computer to devices such as terminals and various peripherals.

Parallel Port 

Parallel port is for connecting an external device such as a printer. Parallel port is also a parallel communication physical interface. It is also known as a printer port. A newer type of parallel port, which supports the same connectors as the Centronics interface, is the EPP (Enhanced Parallel Port) or ECP (Extended Capabilities Port).

FireWall Port

A firewall is a device that controls network traffic. Generally a firewall is configured to block certain inbound ports directed at your local network, but to allow most outbound traffic to travel to the Internet. Holes or conduits are opened through the firewall to allow access to systems on your local network like your web server.

Ethernet Port

Ethernet port is an opening on computer network equipment that Ethernet cable plug into. These ports are alternatively called jacks or sockets. Ethernet ports accept cable with RJ-45 connectors.

High Definition Multimedia Interface(HDMI)

High definition multimedia interface(HDMI) is a compact audio or video interface for transmitting uncompressed digital data. It is a digital alternative to consumer analog standards, such as radio frequency(RF) coaxial cable, composite video, S-Video, SCART, component video,D-Terminal, or VGA. HDMI connects digital audio/video sources (such as set-top boxes, DVD players, HD DVD players, Blu-ray Disc players, AVCHD camcorders, personal computers (PCs), video game consoles such as the PlayStation 3 and Xbox 360, and AV receivers) to compatible digital audio devices, computer monitors, video projectors, and digital televisions.