This document provides information about different types of input devices for computers. It discusses common input devices like keyboards, mice, touchpads, joysticks, touch screens, scanners, optical mark readers, optical character recognition, magnetic ink character recognition, and voice data entry. It describes what each input device is used for and provides examples of how different input devices are used.

1. ICT
WEEK: 2
DATE
CLASS: Year 3
SUBJECT: ICT
LESSON TOPIC: INPUT,PROCESSING
AND OUT
SUB TOPIC: INPUT,FUCTIONS
PERIOD: 2

2. DURATION: 40 Mins
RESOURCES & MATERIALS: computer system,
internet, Wabp, Communication Technology
BUILDING BACKGROUND/CONNECTION TO
PRIOR KNOWLEDGE:
Pupils have been introduced to Input device in their
previous class

3. BOJECTIVES
• At the end of the lesson, pupils should
be able to;
(a)Define input, processing and output
(b)State the examples of input, output
and processing device
(c)Identify and explain each of the
devices

4. 
Data or instructions entered into the memory of
computer
Input device is any hardware component that allows users
to enter data and instructions

INPUT PROCESSING
AND OUTPUT

5. What is a keyboard?


The most common input device
Input device that contains keys users press to enter
data into a computer
Includes alphabetical
keys,numeric
keypad,and function
keys

KEYB
OARD
5

6. THE KEYBOARD -
STANDARD KEYBOARD
LAYOUT
 A standard computer keyboard has about 100 keys.
Most keyboards use the QWERTY layout, named for the
first
six keys in the top row of letters.

7. KEYBOARD
DATA ENTRY
7
• suitable for a wide range of applications
– entering programs
– typing all kinds of documents using a word processor
– entering personal details of customers or patients at a
hospital, etc.

8. THE
MOUS
E
8
What is a Mouse?
• The mouse is a pointing device. You use it to move a
graphical pointer on the screen.
•The mouse can be used
to issue commands, draw,
and perform other types of
input tasks.
• Two characteristics
 Planar movement
 Buttons

9. THE MOUSE - MOUSE
TECHNIQUES
Using the mouse involves five techniques:
1.Pointing: Move the mouse to move the on-screen pointer.
2.Clicking: Press and release the left mouse button once.
3.Double-clicking: Press and release the left mouse button twice.
4.Dragging: Hold down the left mouse button as you move the
pointer.
5.Right-clicking: Press and release the right mouse button.

10. What is a trackball?
 Stationary pointing device with a ball on its
top or side
 A trackball is like a mouse turned upside-
down.
 To move pointer, rotate ball with thumb,
fingers, or palm of hand.
 Separate buttons for picking
 Very fast for gaming
 Used in some portable and notebook
computers.
TRAC
KBAL
L

11. •
•
•
Small touch sensitive tablets
‘Stroke’ to move mouse pointer
Used mainly in laptop computers
• Good ‘acceleration’ settings important
– fast stroke
• lots of pixels per inch moved
• initial movement to the target
– slow stroke
• less pixels per inch
• for accurate positioning
TOUCHPAD

12. – Joysticks are popular for flight
simulator and driving games.
– indirect
pressure of stick = velocity of
movement
– buttons for selection
on top or on front like a trigger
– often used for computer games
aircraft controls and 3D navigation
JOYSTIC
K

13. • Detect the presence of finger or stylus on the
screen.
– works by interrupting matrix of light beams,
capacitance changes or ultrasonic reflections
– direct pointing device
• Advantages:
–
–
–
fast, and requires no specialised pointer
good for menu selection
suitable for use in hostile environment: clean and
safe from damage.
• Disadvantages:
–
–
finger can mark screen
imprecise (finger is a fairly blunt instrument!)
• difficult to select small regions or perform accurate
drawing
lifting arm can be tiring
–
TOUCH-SENSITIVE
SCREEN

14. SCANNERS
•
Converts a document into a series of pixels (picture elements –
these are small squares that, when put together, form a picture).
•
The larger the number of pixels, or conversely the smaller each
individual pixel, the better the definition of the final picture.

15. SCANNERS
• Take paper and convert it into a bitmap
• Two sorts of scanner
– flat-bed: paper placed on a glass plate, whole page converted into
bitmap
– hand-held: scanner passed over paper, digitising strip typically 3-
4” wide
• Shines light at paper and note intensity of reflection
– colour or greyscale
• Typical resolutions from 600–2400 dpi

16. SCANNERS
Used in
– desktop publishing for incorporating photographs and
other images
– document storage and retrieval systems, doing away
with paper storage
+ special scanners for slides and photographic negatives

17. A technology that allows an input device (e.g.
imaging scanner) to read hand-drawn marks
such as small circles or rectangles on
specially designed paper.
• Can recognise the presence of a mark on a
sheet of paper by light reflection.
• The position of the mark conveys information
to the machine.
• Printing is done using a special type of ink
which the optical scanner does not see.
OMR (OPTICAL MARK
READER)

18. • Advantage:
– It is fast, using minimum processing power to process forms
– Costs are predictable and defined
– OMR capture speeds range around 4000 forms per hr
Disadvantage:
– Cannot read paper if folded or dirty.
– Restricted to multi choice questions.
– OMR cannot recognize hand-printed or machine-printed characters.
– With OMR, images of forms are not captured by scanners so electronic
retrieval is not possible.
– Tick boxes may not be suitable for all types of questions
•
OMR

19. • a system that provides a full alphanumeric recognition of printed or
handwritten characters at electronic speed by simply scanning the form.
• Intelligent Character Recognition (ICR) is used to describe the process of
interpreting image data, in particular alphanumeric text.
• Sometimes OCR is known as ICR
OCR

20. MICR
• MICR has several advantages for processing
cheques:
– It is hard to forge the characters
– The characters can be read even if the cheque is
crumpled, dirty or smudged
– The characters are readable by humans, unlike bar
codes

21. BAR CODE READERS
• Bar code readers can read bar codes—patterns of printed bars.
• The reader emits light, which reflects off the bar code and into a
detector in the reader. The detector translates the code into
numbers.
• Flatbed bar code readers are commonly found in supermarkets.
Courier services often use handheld readers.

22. OTHER USES OF
BAR CODES
• Warehousing
– bar coded containers of raw materials are stored in
racks of bins which are also bar coded.
• Transport and distribution
– individual packages are bar coded
• Manufacturing
– work in progress tracked using bar codes

23. MORE USES OF BAR
CODES
• Marketing
– bar coded multiple choice questionnaires
• Medical
– bar codes used to identify blood and other samples
• Libraries
– used to record loans and track stock
• Banking, insurance and local government
– for document control and retrieval.

24. VOICE DATA ENTRY
• The user speaks the text into a microphone
• Special software interprets the text and displays it on a screen
• Text may be edited using the keyboard and exported to a word
processing package such as Word.
• The accuracy of the voice recognition system is improved by ‘training’
it to a particular user’s voice