This document discusses computer input and output. It defines input as any data or instructions entered into the computer's memory via input devices like keyboards, mice, and scanners. Output is the processed results displayed or printed by output devices like computer screens, speakers, and printers. Common input devices described are keyboards, mice, scanners, and microphones, while common output devices are computer screens, speakers, and printers.

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Computer Input and Output
Dairne Jesperson
Charles Darwin University

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Introduction
This presentation aims to:
briefly explain what computer input and output is
examine some of the more commonly used input
and output devices to help understand these
concepts.

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Input
Input is any data or instruction that is entered
into the computers memory.
Input devices are the hardware components that
you use to enter the data or instructions into the
computer.

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Output
Output is a result of:
– inputting data into the
computer
– the computer processes
the data
– the computer sends out
the processed
information by means of
an output device
Output can be displayed:
– on screen,
– printed out,
– in the form of graphics, or
– voice or sound output.

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Devices
Input Devices
Keyboard
Mouse
Scanner
Joystick
Microphone
Digital camera
Output Devices
Computer screen
Speakers
Printer
These are just a few of the input and output devices you may recognise

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Keyboard
A particular key is pressed,
sending an electronic signal
to the computers ‘brain’.
The computers ‘brain’
interprets the signal.
The computer sends back a
particular letter or character
which represents the signal
that the computer has
interpreted.

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Mouse
Controls the movement of the cursor on the
screen – as you move the mouse, the cursor
moves in the same direction.
Useful in graphics programs where you can draw
pictures by using the mouse as a pen or
paintbrush.
So called because of it’s shape – the wire
connecting it to the computer being it’s tail.

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Scanner
Scans a picture or text.
Translates information into a form the computer
can understand.
This information can then be
– displayed on the computer screen
– stored to a file
– used in computer documents

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Computer Screen
The most obvious and
useful output device,
displaying text and
graphics as you are
working on them.
Can display still or moving images.

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Speakers
Speakers output sound from
your computer.
The speakers take the
electronic signals stored on
things like CD’s and DVD’s
and and send them out as
the sound we can hear.

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Printer
This device is used for outputting text or images
onto paper.
Different kinds of printers produce different
quality output.
Laser and ink-jet printers produce
the highest quality documents.

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To Summarise…
Machines that let you enter data are input
devices
Machines that show you the data in a form
you can understand are output devices.