there are the full description of output, processing and communication hardware.

1. The output
devices

2. Definition
An output device is any device used to
send data from a computer to another
device or user. Most computer data
output that is meant for humans is in
the form of audio or video. Thus, most
output devices used by humans are in
these categories. Examples include
monitors, projectors, speakers,
headphones and printers.

3. The work and types:
Works:
 Receive data from the forecasting unit
 Convert the computer language into
human language.
Types:
 Hardcopy
 Softcopy

4. Hardcopy output devices :
Printer:
The printer is a common output device. It
produces permanent visual record of the
output from a computer. Printers can be
subdivided into two broad categories. They
are –
 Impact printer
 Non-Impact printer

5. Impact printer:
In an Impact printer printing occurs as a result
of hammer striking a character from and the
character from in turn striking an inked
ribbon causing the ribbon to press an image
of the character on paper.
Impact printer is two types –
1. Dot matrix and
2. Daisy wheel printer

6. Dot matrix printer:
A type of printer that produces characters and
illustrations by striking pins against an ink
ribbon to print closely spaced dots in the
appropriate shape. Dot-matrix printers are
relatively expensive and do not produce high-
quality output. However, they can print to
multi-page forms (that is, carbon copies).

7. Daisy-wheel printer:
A type of printer that produces letter-quality
type. The daisy wheel is a disk made of plastic
or metal on which characters stand out in
relief along the outer edge. To print a
character, the printer rotates the disk until the
desired letter is facing the paper.

8. Non-Impact printer:
A type of printer that does not operate by
striking a head against a ribbon.
Non impact printer is three types –
 Ink-Jet printer
 Laser printer
 Thermal printer

9. Ink-Jet printer:
A type of printer that works by spraying
ionized ink at a sheet of paper. Magnetized
plates in the ink's path direct the ink onto
the paper in the desired shapes. Ink-jet
printers are capable of producing high
quality print.

10. Laser printer:
A type of printer that utilizes a laser beam to
produce an image on a drum. The light of
the laser alters the electrical charge on the
drum wherever it hits. The drum is then
rolled through a reservoir of toner, which is
picked up by the charged portions of the
drum. Finally, the toner is transferred to the
paper through a combination of heat and
pressure. This is also the way copy
machines work.

11. Laser printer:

12. Thermal printer:
Thermal printer use heat to produce an image
on special paper. The print mechanism, like
a dot matrix print head, is designed to heat
the surface of chemically treated paper and
a dot is produced based on the reaction of
the chemical to heat. No ribbon or ink is
involved.

13. Plotter:
The plotter is alike the printer it is the wide
version of printer. A plotter gives a hardcopy
of the output.
There are different types of plotter. They are
–
 Pen plotter
 Electronic plotter
 Thermal plotter

14. Pen plotter:
Pen plotters print by moving a pen or other
instrument across the surface of a piece of
paper. Pen plotters can draw complex line
art, including text, but do so slowly because
of the mechanical movement of the pens.

15. Electrostatic plotter:
Electrostatic plotters used a dry tonner
transfer process similar to that in
many photocopiers .They were faster than
pen plotters and were available in large
formats, suitable for reproducing
engineering drawings.
Thermal plotter:
The thermal printer works as like as the
thermal printer.

16. Softcopy output devices :
Monitor:
Monitor is one of the important output devices
of computer. It looks like a television
screen. It is a media of displaying texts,
images, graphics, videos and any other
information on its screen.
Monitors are may be two categories based on
technologies. They are-
 CRT
 Flat panel – (LCD, LED, Plasma)

17. CRT monitors:
A CRT is a big glass bottle with a vacuum
tube inside contains three guns that squirt
out focused beams of electrons.
Flat panel:
LCD:
Full name of Liquid Crystal Displays. It is thin,
compact, lightweight and sometimes
referred to as a flat panel display screen. It
has no tubes, electronic guns etc like CRT.

18. LED:
An LED monitor (short for Light Emitting Diode) or
LED display is a flat screen, flat panel computer
monitor or television. It has a very short depth and
is light in terms of weight. The actual difference
between this and a typical LCD monitor is the
backlighting.
Plasma:
A plasma display is a computer video display in
which each pixel on the screen is illuminated by a
tiny bit of plasma or charged gas, somewhat like a
tiny neon light. Plasma displays are thinner than
cathode ray tube ( CRT ) displays and brighter
than liquid crystal displays ( LCD ).

19. Monitors:

20. Monitor can be classified into three
categories based on showing colors:
Monochrome:
Display only one colour against a contrasting. These
type of monitors are used for displaying only text and
when colour graphics are required to display.
Grayscale:
These are essentially types of monochrome monitors
that display gray against white or off-white
background.
Color monitors:
This types of monitors display 16 colours to 16 million
colours. Most of the monitors of today are colour
monitors.


21. Processing
Devices

22. Definition:
When a computer receives data from an input
device, the data must go through an
intermediate stage before it can be sent to
an output device, like a monitor, printer, or
speakers. A processing device is any device
in a computer that handles this intermediate
stage, being responsible for controlling the
storage and retrieval of data.

23. Some of the most common processing
devices in a computer include the
following:
 Central processing unit (CPU)
 Graphics processing unit (GPU)
 Motherboard
 Network card
 Sound card

24. CPU:
CPU (pronounced as separate letters) is the
abbreviation for central processing unit.
Sometimes referred to simply as the central
processor, but more commonly called
processor, the CPU is the brains of the
computer where most calculations take place.
In terms of computing power, the CPU is the
most important element of a computer
system.

25. The components of CPU:
Control Unit:
The control unit (CU) is a component of a
computer's central processing unit (CPU)
that directs operation of the processor. It
tells the computer's memory,
arithmetic/logic unit and input and output
devices how to respond to a program's
instructions

26. The components of CPU(cont):
Arithmetic logic unit:
The arithmetic logic unit (ALU) is a digital circuit
within the processor that performs integer
arithmetic and bitwise logic operations.
Cache:
Pronounced cash, A special high-speed storage
mechanism. Cache can be either a reserved
section of main memory or an independent high-
speed storage device. Two types of caching are
commonly used in personal computers: memory
caching and disk caching.

27. GPU:
Short for Graphics Processing Unit, GPU is an
electronic circuit used to speed up the
creation of both 2D and 3D images. By
having a separate processor, the GPU allows
the computer's CPU resources to be used for
other important tasks. In the picture is an
example of a GPU on a video card without
the heat sink.

28. GPU (cont):
Graphics card :
A graphics card is a mechanical device built
into a computer that enables the user to
see graphics and video faster and clearer.
Video adapter:
A board that plugs into a personal computer
to give it display capabilities. A
monochrome monitor, for example, cannot
display colors no matter how powerful the
video adapter.

29. GPU (cont):
Display adapter:
A plug-in card in a desktop computer that
performs graphics processing. Also called a
"video card" or "graphics card" . The display
adapter determines the maximum resolution,
refresh rate and number of colors that can be
displayed, which the monitor must also be
able to support.

30. Expansion Card:
An expansion card is an electronic card/board
that is used to add extra functionality to a
computer. It is inserted into an expansion
slot on the motherboard of a computer.
Expansion cards contain edge connectors
that are used to create an electronic link
between motherboard and card, thus
enabling these two to communicate.

31. Motherboard:
The main circuit board of a microcomputer. The
motherboard contains the connectors for
attaching additional boards. Typically, the
motherboard contains the CPU, BIOS,
memory, mass storage interfaces, serial and
parallel ports, expansion slots, and all the
controllers required to control standard
peripheral devices, such as the display
screen, keyboard, and disk drive. Collectively,
all these chips that reside on the motherboard
are known as the motherboard's chipset.

32. Motherboard:

33. NIC - network interface card:
Short for Network Interface Card, the NIC is also
referred to as an Ethernet card and network
adapter. It is an expansion card that enables a
computer to connect to a network; such as a
home network, or the Internet using an
Ethernet cable with an RJ-45 connector.

34. Sound Card:
A sound card is an expansion component used
in computers to receive and send audio.
Sound cards are configured and utilized with
the help of a software application and a
device driver. The input device attached to
receive audio data is usually a microphone,
while the device used to output audio data is
generally speakers or headphones.

35. Communication
devices

36. Definition:
A communication device is a hardware device
capable of transmitting an analog or digital
signal over the telephone, other
communication wire, or wirelessly. The best
example of a communication device is a
computer Modem, which is capable of
sending and receiving a signal to allow
computers to talk to other computers over the
telephone. Other examples of communication
devices include a network interface card
(NIC), Wi-Fi devices, and an access point.
Below is a picture of some of the different
types of Wi-Fi devices that are all examples of
a communication device.

37. Bluetooth:
Bluetooth is defined as being a short-range
radio technology (or wireless technology)
aimed at simplifying communications
among Internet devices and between
devices and the Internet. It also aims to
simplify data synchronization between
Internet devices and other computers.

38. Modem:
Short for modulator-demodulator. A modem is
a device or program that enables a
computer to transmit data over, for example,
telephone or cable lines. Computer
information is stored digitally, whereas
information transmitted over telephone lines
is transmitted in the form of analog waves. A
modem converts between these two forms.

39. Router:
A router is a device that forwards data
packets along networks. A router is
connected to at least two networks,
commonly two LANs or WANs or a LAN
and its ISP's network. Routers are located
at gateways, the places where two or more
networks connect.

40. Wi-Fi:
Wi-Fi is the name of a popular wireless
networking technology that uses radio
waves to provide wireless high-speed
Internet and network connections. A
common misconception is that the term Wi-
Fi is short for "wireless fidelity" .

41. Analog Telephone Adapter:
A phone handset-to-Ethernet adapter that
allows traditional (analog) telephone devices
to be used with Voice Over IP (VOIP)
services and equipment. The adapters are
roughly the same size as a home Internet
router and contain one or more traditional
phone jack ports. The analog phone plugs
into the adapter, which then communicates
with an Internet router via an Ethernet
connection.