Hardware: the machines, wiring, and other physical components of a
A digital computer’s hardware is a complex system of four functionally
different elements-a central processing unit, input devices, memory-storage
devices, and output devices-linked by a communication network, or bus. The
bus is usually incorporated into the main circuit board, called the
motherboard, which is plugged into all the other components.
The central processing unit: the part of a computer in which operations are
controlled and executed.
The heart of a computer is the central processing unit, or CPU. In addition
to performing arithmetic and logic operations on data, it times and
controls the rest of the system. Mainframe and supercomputer CPUs sometimes
consist of several linked microchips, called microprocessors, each of which
performs a separate task, but most other computers require only a single
microprocessor as a CPU.
Input device: Components known as input devices let users enter commands,
data, or programs for processing by the CPU.
Output device: Components that let the user see or hear the results of the
computer’s data processing
Motherboard: a printed circuit board containing the principal components of
a microcomputer or other device, with connectors for other circuit boards
to be slotted into.
Heat sink: a device for absorbing excessive or unwanted heat of the
Fan: an apparatus with rotating blades that creates a current of air for
RAM: random-access memory
Hard disk: a rigid non-removable magnetic disk with a large data storage
CD Rom: a compact disc used in a computer as a read-only device for
VGA: video graphics array, a standard for defining colour display screens
Sound card: a device which can be slotted into a computer to allow the use
of audio components for multimedia applications.
Modem: a device for interconverting digital and analogue signals,
especially to enable a computer to be connected to a telephone line. It
can also be used to send data.
Network card: Is used to operate with a network, to operate interactively;
Interact with others to exchange information and develop useful contacts.