Transcript Ch. 2 Idea of Stored Data and Stored Program

2.1 Idea of Stored Data
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Data is a collection of raw facts which may be
represented by numbers, text, graphics, etc.
They become meaningful after being processed.
The processed data is called information.
299 792 458
Stephen Hawking
Number
Text
Graphics
Three main types of data: number, text and graphics
2.1 Idea of Stored Data
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We have to deal with a lot of data everyday, for
example, date of birth, weight, height and
telephone numbers.
To use data repeatedly, we need to store it.
By memory
By handwriting
By computer storage
Three ways of storing data
2.1 Idea of Stored Data
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A shopping checklist can be stored, e.g.:
◦ on paper
◦ in a PDA
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The checklists are examples of stored data.
Data can be managed and reused more efficiently
if it is organized and stored appropriately.
Kevin write
down his
shopping
checklist on a
paper.
Susan uses a
PDA to write
down
the shopping
checklist.
Examples of stored data in our daily lives
2.2 Idea of Stored Program
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A program consists of a series of commands,
which can instruct the computers to perform a
specific tasks.
Computer operate according to the order of the
commands.
It is important to write the commands in a correct
order. Otherwise, the computers cannot perform
the specific task successfully.
2.2 Idea of Stored Program
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Stored programs are used to perform certain
specific or repeated tasks, e.g.
◦ preset programs stored in video recorders and washing
machines
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With stored programs, computers can perform
tasks automatically and repeatedly.
Computers can relieve us of tedious tasks such as
calculation and machine control.
Use a remote control to
set the recording
schedule
Activity 3
Passing through the maze
Can you instruct a robot to pass through the
following maze?
Exit
Entrance
Rule: You may use
a pencil to draft
your route first
and then analyze a
series of
commands for the
robot.
Activity 3
Passing through the maze
Command
01
10
11
Task
Turn left
Turn right
Step forward
The above table shows the commands which
control the robot’s actions. Write down the
program which will direct the route of the robot.
Activity 3
Passing through the maze
11  11  10  11  01  11  10 
11  10  11  11  01  11  11 
11  01  11  11  11  01  11 
11  11  10  11  10  11  11
11  01  11  11
2.3 Storage Device
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another type of computer hardware
used for storing data and programs
Input device
Central processing unit
Output device
Storage devices
CompactFlash card
Hard disk
USB flash disk
Floppy disk
SD card
Memory Stick
CD-ROM
The relationship among input devices, central processing unit,
output devices and storage devices
Activity 4
Understanding storage device
Different storage devices work with different equipment. Try to
match them correctly.
Digital camera
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Smart card reader
SIM card
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Octopus reader
SD card
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Mobile phone
Smart Identity
Card
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Floppy disk
DVD
Octopus card
Floppy disk drive
DVD player