This document discusses various input and output devices used with computers. Input devices allow users to interact with the computer by entering data or instructions, such as keyboards, mice, scanners, joysticks, microphones, and webcams. Output devices allow the computer to communicate information to users through displays, such as monitors, printers, speakers, projectors, and actuators. Together, input and output devices facilitate interaction between humans and computers.

1. I/O Devices
Input and Output Devices

2. Input Device
 An input device is any piece of hardware that allows
us to send data or information to a central
processing unit of a computer.
 Input devices helps human to either interact with or
control the computer.
 So if you type a message on a keyboard or touch a
screen to make something happen you're using an
input device.

3. Keyboard
 The keyboard has 104 keys.
 They are alphabet keys, number keys, function keys,
arrow keys, enter key, etc.
 By pressing the relevant keys, a user can enter data
and instructions to the computer.

4. Mouse
 A mouse interacts with a computer through a process
known as point and click.
 When a user moves the mouse, the pointer moves in a
corresponding direction on the computer's monitor
screen.
 A mouse can be wired or wireless. Scanner A scanner
is an input device that is used to transfer images or text
from books or paper into a computer.

5. Scanner
 A scanner is an input device that is used to
transfer images or text from books or paper
into a computer.

6. Joystick
 A joystick is an input device often used to control
video games.
 A joystick consists of a handle that pivots on a base
and sends its angle or direction to the computer as
data.

7. Microphone
 A microphone is used to record our voice and
different sounds into a computer.
 It also helps us to chat with our friends through
internet.

8. Light pen
 Light pen allows the user to point to
displayed objects on the computer
screen.
 It is used to write or draw on the
computer screen.

9. Webcam
 Webcam is an input device
connected to the computer and
can capture photographs and
videos.
 Webcams are more often used to
live stream videos or perform
video chats.

10. Sensor
 An input device that takes readings
from the environment such as
temperature, light and motion.
Obviously, each type of sensor works in
a completely different way.
 An example of where this could be used
is a thermostat that detects temperature
and turns your heating on or off.

11. Output Device
 An output device on the other hand is any piece of
hardware that allows a computer to communicate
information to us.
 An output device receives data or information from
the central processing unit.
 Using the output devices, a computer can interact
with the human.
 For example displaying a message on a screen,
playing sound via a speaker or headphones or
printing a document.

12. Monitor
 A device that outputs a visual display of
the user interface of any software that
is currently being used on the
computer.
 We use it so we can see the data we
are working with and can interact with
it.
 Without the monitor, we wouldn’t be
able to see the effect of our inputs.

13. Printer
 It can print both in black and white, or color.
 The printed copy on a paper is called the hard copy.

14. Plotter
 Plotter is an output device much like a printer.
 Instead of toner, plotters use a pen, pencil, marker,
or another writing tool to draw multiple continuous
lines onto paper.

15. Speaker
 Speaker allow us to listen to music, and hear sound
effects stored in a computer.

16. Headphones
 Headphones are used to
listen to music as well as
record sounds without
disturbing others.

17. Projector
 A projector is an output device that projects an
image from the computer onto a large surface, such
as a white screen. Question time.

18. Actuator
 An output device that produces motion.
 We use it to control or move things.
 They are commonly used with sensors.
 An example could be an actuator that turns
our heating on or off.
 There are different types of actuators that
produce different motion and that can affect
the measures of performance.