IGCSE_ICT_Presentation.pptx about the chapter 5

CIE IGCSE INFO. COMM. TECH. //0417
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TABLE OF CONTENTS
3
CHAPTER 1
Types and Components of Computer Systems
7
CHAPTER 2
Input & Output Devices
17
CHAPTER 3
Storage Devices & Media
19
CHAPTER 4
Networks & the Effects of Using them
25

Types and Components of Computer Systems
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54
CHAPTER 11
File Management
54
CHAPTER 12
Images
54
CHAPTER 13
Layout
54
CHAPTER 14
Styles
54

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1. TYPES AND COMPONENTS OF COMPUTER
SYSTEMS
1.1 Hardware & Software
Hardware
• Tangible physical components of a computer system
• You can feel it or touch it
• Internal Hardware Devices:
o Processor
o Motherboard
o RAM & ROM
o Video & Sound Cards
o Internal Hard Disk Drives
• External Hardware Devices:
o Monitor
o Keyboard
o Mouse
o Printer
o External Storage Devices
Software
• Programs that control computer systems
• Set of instructions that make computer do something
• You cannot physically touch software
• Relates to ideas & instructions for using physical objects

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• Input devices:
o Purpose is to provide data for processing
o Data is raw facts which alone have no meaning
o Examples: keyboard, mouse
• Output devices:
o Displays result of processing
o Information is processed data which has been given
meaning
o Examples: monitor, printer
Secondary/Backing Storage
• Stores data/information & programs not being used at
current time
• Backing store device = reader or recorder
o Example: Hard disk drive
• Backing store media = hardware containing data
o Example: Hard disk
Basic Computer Model
1.3 Operating Systems
• Enables users to communicate with computer systems
• Controls operation of input, output & backing storage

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• Disadvantages
o Not portable since they are made up of separate
components
o Wiring clutters up desk space
o Necessary to copy files as they aren't portable
Laptop/Notebook Computers
• Refers to computers where monitor, keyboard, pointing
device and processor together in a single unit
• Extremely portable systems
o Low weight
o Low power consumption
o Processor doesn't generate too much heat
• Advantages
o Portable because monitor, pointing device, keyboard,
processor & backing store units are together in one box
o No trailing wires
o Full advantage of Wi-Fi
o Can link into any multimedia system
• Disadvantages
o Easy to steal
o Limited battery; need to carry charger
o Keyboard and pointing device awkward to use
o Heat dissipation is difficult due to laptop structure

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Biometrics
• A part of a person’s body is used to identify that
individual
• Can be:
o Fingerprints
o Retina
o Iris
o Face
o Voice
• These are all unique to everyone thus can be used as an
authentication technique
• Must be added initially to a system to use as
identification
• Impacts on everyday life:
o Better security at the airport since most use at least
one form of biometric check if not more
o Increased security in certain places as only authorized
personnel can gain entry
o Reduced vehicle theft since newer car doors come
with a fingerprint lock on the door handle
o More secure mobile devices as most now have some
sort of biometrics integrated into them
Vision Enhancement

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• Different laser beams are used to record the 2D images
onto a single photographic plate
• This creates an illusion of one 3D images
• Impact on everyday life:
o Improved security since majority of credit/ID cards &
bank notes use holograms to prevent forgery
o Better movie experiences since 3D viewing can provide
a more immersive experience for the audience
o Greater data storage since holographic layers can
potentially decrease the thickness of disc storage
Virtual Reality (VR)
• When computers create an artificial environment that
users can virtually interact with
• Uses:
o Allow architects to walk around a virtual version of
their design
o Training soldiers for combat by allowing them to fight
against virtual enemies
o Training surgeons by allowing them to operate on
virtual patients
o Playing games and enhance the level of immersion
• General VR equipment:
o Eye goggles that produce 3D images to develop the

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• Disadvantages
o Can be difficult to use due to the very small keys
o Difficult to use for entering text
o Sometimes the order of numbers isn’t very intuitive
Mouse
• An example of a pointing device
• The ball underneath the mouse is used to detect
movement
• The left button is for selecting by double on it and the
right is to bring drop-down menus
• There is usually a scroll button which speeds up the
process of moving through a document
• Uses
o Used for opening, closing and minimising software
o Used for grouping, moving and deleting files
o Useful when editing images (e.g. controlling the size
and position of the image)
o Used for controlling the position of a pointer on the
screen to allow:
▪ Selection from a menu
▪ Selecting an icon
▪ Scrolling up/down and right/left
• Advantages

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Remote Control
• A remote control is used to control the operation of
other devices remotely by using infra-red signals
• Uses
o In home entertainment devices such as Televisions,
DVD player/recorder and satellite system
o Used to control multimedia systems
o Used in industrial applications to remotely control
processes, stop and start machinery
• Advantages
o Enable devices to be operated from any distance,
which is useful for people with disabilities
o Some chemical processes are hazardous, so it is safer
to operate equipment from a distance
• Disadvantages
o People with limited hand/wrist movement can find
them hard to use
o The signal between the control and the device can be
easily blocked
Joystick
• By gripping the stick, a pointer
on the screen can be controlled
• Buttons are used to make

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Digital Cameras
• Photographs are stored in memory
• They can be easily transferred to a computer using a USB
• Uses
o Digital cameras can produce
photographs for direct transfer
to a computer or to print out
o Digital cameras allow short
video clips to be produced
o Photographs can be uploaded directly into application
software such as word processor
• Advantages
o Easier to produce better quality photographs than
with a tradition camera
o Easier and faster to upload photographs to a computer
o There is no need to develop film and print out
photographs (saves paper and no longer needs the
chemicals to produce photographs from films)
o Easy to delete an image from the memory if it’s not
satisfactory
o The memory card can store several hundred
photographs
• Disadvantages

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Graphic Tablet
• A graphic tablet is used with a stylus to produce
freehand drawings
• Uses
o Graphics tablets are used to
produce drawings, computer
graphics
o In countries where characters are complex e.g. japan
they are used as a form of input
o They are used in computer aided design (CAD) work
• Advantages
o It is possible to modify drawings before they are input
o They offer an accurate method of drawing
• Disadvantages
o They are more expensive than other pointing devices
Video Camera
• DV (digital video) camera store compressed photo
frames at 25 MB/s – motion jpeg.
• Light turned into electronic signal through light sensitive
sensors and automatically converted to a digital file
format.
• Advantages:

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• Advantages
o Provide a more secure payment system than requiring
a signature or using magnetic stripe, since the PIN
typed in must match up with the PIN stored on the chip
o Provide a more robust system than magnetic stripe
since the chip does not need to be in contact with the
reader
• Disadvantages
o Customer needs to be careful when typing in the PIN,
so nobody reads it giving an opportunity for Fraud
Radio Frequency Identification (RFID) Readers
• RFID readers work in similar ways to a bar code reader
• An RFID tag is attached to/inside a surface
• The reader reads the data held on the tag which is then
input into the computer system for processing
• Radio waves are used to transmit data thus can be used
through most materials
• Uses
o Used in retail or supermarkets as barcode alternatives
o Used to identify pets
o Used in passports
• Advantages
o Can hold a lot of data

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Barcode readers
• Used to read information in the
form of a barcode
• Handheld scanners or wands are
very common for reading
barcodes
• Uses
o Used in supermarkets and other shops where the
goods are marked with a barcode
o Used in libraries to scan user’s library card and
barcodes on books (to keep track of books on loan)
o Used as a safety function in many companies to ensure
that electrical equipment is checked on a regular basis
• Advantages
o Faster than keying in information, and fewer mistakes
are made
o Used as a way of recording data, can improve safety
o Barcodes enable automatic stock control
o Barcode scanning is a tried and trusted technology
o When an item price is changed, only the central
database needs to be updated, there is no need to
change the prices individually on each item
• Disadvantages

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IPS/LCD Monitor
• Front layer made from liquid crystal diodes; grouped
together to form pixels (RGB or RGBY-more vivid colours)
• Receive analogue and digital signals, although most
modern projectors only work with digital inputs
• IPS (In-plane switching) is the technology used in LCD
monitors.
• Advantages:
o Colour can be seen accurately from different viewing
angles
o No lightening on touching
• Disadvantages:
o Expensive
o High power consumption
o Slow response time
• Note: Old LCD monitors used CCFL (cold cathode
fluorescent lamp) technology to light up the screen.
LED Monitor:
• Front layer made from liquid crystal diodes; grouped
together to form pixels (RGB or RGBY-more vivid colours)
• For the image to show up on-screen a light source of LED
backlight is used.
• Advantages (over LCD monitors):

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• Uses
o Used where noise levels need to be kept low e.g. in an
office
o The best option for fast, high quality, high volume
printing
• Advantages
o Printing is fast for high volumes, slightly faster than
inkjet if only a few pages are to be printed
o Can handle very large print jobs
o Quality is consistently high
o Toner cartridges last for a long time; laser printers can
be a cost-effective option if colour outputs are not
required
• Disadvantages
o Expensive to buy
o Only fast if several copies are being made
o Colour laser printers tend to be expensive to run since
four cartridges are needed as well as diffuser kits, etc.
o Produce ozone and volatile organic compounds
because of their printing method and type of toner/ink
used
o These have been linked to health hazards in the office
Inkjet Printer

Storage Devices & Media
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• Uses
o Used to produce large drawings e.g. blueprints of
buildings; are often used with CAD applications
o Used to produce large pictures for use on billboards or
giant posters
▪ They can also print on plastic coated paper
• If the pens are replaced by cutting tools, it is possible to
make large signs
• Advantages
o Can produce huge printouts
o Print quality is extremely high
• Disadvantages
o Slow in operation
o Expensive to buy and maintain
3D Printer
• A new type of printer that
produces solid 3D models using
modified inkjet technology called
tomography
• Very thin layers of fine powder
(plaster, resin, starch) are bonded together as a 3D
model is slowly built up
• Items produced are known as prototypes

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Motors
• Turned on or off by the actuator
• Uses
o Used in many domestic appliances
o Automatic washing machines (to
make the drum rotate)
o Cookers (to switch on fans)
o Water pumps in central heating systems
o Automatic greenhouses to open windows and switch
on fans
o Used to control robot arms in the industry
o Operate fans, disk drives and DVD drives in computers
Buzzers
• Switched on or off by the actuator
• Uses
o Used in cookers and microwave ovens to tell the
operator when the cooking process is complete
o Used in burglar alarm systems to warn if intruders are
present
Heaters
• Actuators are connected to switches which turn the
heater on or off
• Uses

Networks & the Effects of Using Them
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• Disadvantages
o Access time is very slow
o When updating another tape is needed
Memory Cards
• A form of electrically erasable programmable read only
memory (EEPROM)
• Uses
o Used to store photos on digital cameras
o Mobile phones use them as memory cards
o Used in MP3 players to store music
o Used as a backup in hand held devices
• Advantages
o Very compact
o Very robust
• Disadvantages
o Very expensive per Gb of memory when compared to
hard drive disks
o Has a finite life in terms of the number of times they
can be read from/written to.
3.2 Optical Backing Storage Media
CD-ROM/DVD-ROM
• Read only memory – cannot be overwritten
• Data is stored as a series of pits and lands formed by a

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• Uses
o DVD-RAMs are used in recording devices such as
satellite receivers to allow simultaneous recording and
playback
o They are used in camcorders to store films
• Advantages
o Have a long life (30 years)
o Can be re written on more than the DVD-RWs
(100,000 times)
o Very reliable as they have built in verification software
to ensure accuracy of data
o Access is very fast
o No need to finalize the disk
o Very large capacities
o Ability to read and write data at the same time
• Disadvantage
o DVD-RAMS are not as compatible as R or RW, many
systems will not recognize this format
o More expensive than DVD-RW
Blu-Ray Discs
• Uses
o Blu-ray disks are used in home video consoles
o Used for storing and playing back films

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Function
• Makes decisions on messages being passed between the
networks
• Reads information about the message and decides
where the message should go and the best route for it to
get there
• Formats the messages making it suitable for the new
network
How it Works
• To send data to a specific device, a router needs a
something like an address
• Internet Protocol Address: a unique number assigned to
all computers and devices connected to the internet
which can determine its exact physical location
• A router can use this IP to send data from the internet to
the exact device that requested it
• Storing IP Addresses:
o Routers store IP addresses in a routing table
o Routing tables list all the different routes to other
networks
o Routing table determines best route for data
Sending Data between Devices
• Routers can also send ‘packets’ of data between devices

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4.3 Wi-Fi & Bluetooth
Wi-Fi
• Any system which allows you to connect to a network or
computer through wireless communication
• Examples:
o WLANs
o PDAs
o Laptop computers
o Peripheral devices such as printers
• Wi-Fi Hotspots
o Wi-Fi systems rely on AP (radio frequency technology)
to enable the device to receive and send signals
o Wi-Fi hotspots are places where you can access Wi-Fi
(free or paid)
o Hotspots are found in public places like Airports,
hotels, and cafés
o War driving: The act of driving and searching for
unsecured Wi-Fi hotspots
o This gives a risk to the Wi-Fi system
Bluetooth
• Bluetooth is an example of wireless personal area
networking (WPAN) technology
• Spread spectrum transmission (radio waves) is used to

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4.7 Internet Service Provider (ISP)
• These are companies that provide users with access to
the internet
• Provider in return for these services is charged a monthly
or annual fee
• After paying this fee, a username and password are
issued which can be used to connect to the internet
4.8 Common Network Environments
Internet
• A worldwide collection of networks and computers that
have joined together
• Uses of the Internet:
o Web Browsing
o Email
o File Sharing
o Entertainment
o Video Conferencing
o Online Banking
o Advertising & Blogging
o Social Media
Intranet
• Like the internet but only accessible to specific users
• Basically, a private internet where outsiders cannot

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4.9 Using Different Types of Computers to
Access the Internet
LAPTOP COMPUTERS
ADVANTAGES
DISADVANTAGES
• More portable than
desktops can access internet
in more locations
• Larger screen than tablets &
smartphones which allows
easier reading
• Keyboards are bigger than
those on
tablets/smartphones
• Touchpads allows easy
navigation even on slanted
surfaces
• Less portable than
tablets/smartphones
• Screens not as large as
desktop PCs may not appear
as clearly
• CPUs are not as powerful as

The Effects of Using ICT
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4.11 Password Interception
Spyware
• Spyware is software that gathers user information
through their network connections without them being
aware that this is happening
• Once spyware is installed, it monitors all key presses and
transmits the information back to the person who sent
out the spyware
• This software can install other spyware software, read
cookies and personal information, and change the
default home page or web browser
• Anti-spyware can be used to search out this software
and correct the corruption
Weak & Strong Passwords
•
Strong passwords: A random mix of alphabets
(uppercase and lowercase), numbers, and keyboard
symbols (@, %, ^ etc.)
•
Weak passwords: Easy to guess, e.g. users name or
date of birth or 1234556, etc.
• Frequent password changes can help reduce the chances
of password interception too

ICT Applications
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• Fax/modem software in the computer converts the
image into a form fax machines can be recognized
• Physical Faxing: dedicated fax machine connected via
telephone line that copies and electronically sends files
to the dialled recipient
• Electronic Faxing/Online Faxing: uses the internet to
send documents through computers.
PHYSICAL FAXING
ELECTRONIC FAXING
Associated with a phone
no. Only
Associated with an email
address and phone no.
Need actual fax machine,
paper, etc.
Cheaper- no fax machine,
paper and ink
No encryption
Better safety- encryption
The signal can get busy
No busy signal issues
Email

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Effect on Companies:
• Can employ less people
• Robots do not take holiday, get sick or need breaks
• Greater consistency in products made
5.2 Effects of IT on Working Patterns
• Part-time working: A contract where someone works
fewer hours per week than a full-time employee, in
shifts.
• Flexible working (flexi-time): Workers can choose their
working time but will have to complete the day’s work.
• Job sharing: Two or more part-time workers divide their
job, replacing one full-time worker.
• Compressed hours: Employees can work longer hours
per day but over fewer days, completing the workload
sooner.
5.3 Microprocessor-Controlled Devices in the
Home
POSITIVE EFFECTS
NEGATIVE EFFECTS
• Lead to more leisure time
since devices can be
programmed to do tasks
• More time to socialize

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• Disadvantages
o Requires distribution
o There are no special effects; sound/video/animation
o There are printing costs; paper/ink
Websites
• Collection of webpages, text, graphics, video and sound
• Hosted on a web server on the internet
• Need to write code or use a web authoring application
• Hyperlinks to other pages can be added
• Interactive websites require programming knowledge
• Can use a camera, scanner, microphone to input data
• Usually hire space from web hosting company
• Advantages
o Ability to add sound/video/animation
o Links to other websites/hyperlinks
o The use of hot spots
o Buttons to navigate/move around the website
o Hit counters to see who has visited the websites
• Disadvantages
o Can be hacked and modified or viruses introduced
o Need for a computer and internet connection
o Lack of portability compared with paper based system
o Need to maintain website once it is set up

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• Used for communication via
o Phone calls
o Text messaging
o Social Media
Internet Telephony/VOIP
• VOIP (Voice over internet protocol) is a method used to
talk to people over internet
• VOIP converts sound (picked up by a microphone) into
discrete digital packets that can be sent to a destination
via the internet
Publicity & Corporate Image Publications
• Business Cards:
o Miniature printed documents that provide information
about the business/organisation
o Usually printed on thick cards
o Easily distributable to potential clients
o Information includes company logo, services, address,
contact numbers, email, website
o Gives a professional impression
• Letterheads:
o Found at the top of official printed documents to be
mailed to clients or for internal use
o Makes it clear to reader who the sender is

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Clubs & Society Records
• Need to keep a record on members usually in a database
• Usually payment details, contact details and interests
• It makes it easy to match people with interests and send
information about what they are interested in
• This can be done my using mail merging
• Easy to check memberships and send out reminders
• It is important to follow the data protection act
School Reports
• Database applications such as SIMS store large amounts
of data which can be used to create annual and termly
school reports
• Things able to be gathered from here are:
o Data individual to student – tests/exam results
o Student progress – target grades being met or not
o Number of absences – create a percentage of amount
of days attended school
o Teacher comments – adds comments on to report
6.3 Measurement Applications
• Sensors are used to send data to a computer where the
data is processed
• The computer simply reviews the data from the sensors
(by comparing it to data stored in memory) and updates

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• The system continues to monitor the patient until the
computer is turned off
Advantages of Using Computers in Measurement
• The computer will not forget to take readings
• The computer’s response time is much faster, which is
particularly important in the patient monitoring example
• Doctors, nurses, scientists, etc. can all get on with other
tasks while the monitoring is done automatically
• Computer give 24 hours cover every day (i.e. 24/7)
• The readings will tend to be more accurate
• Readings can be taken more frequently if they are done
by a computer and sensors
• It could also be safer if whatever is being monitored may
have potential hazards (e.g. children falling into the river
whilst attempting to take readings)
Disadvantages of Using Computers in Measurement
• Expensive to purchase and set up
• If performed for educational purposes, reduced practical
hands-on experience and learning.
• Will not function in a power cut if no backup power
present (expensive to have reliable backup power)
6.4 Microprocessors in Control Applications
• Sensors are used to send data to a computer where the

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Central Heating System
• Applying factors
o Inputs
▪ Inputs from the user
➢ Room temperature required
➢ Time systems turns on/off
▪ Inputs from the system
➢ Actual room temperature
➢ Clock giving the time
o Outcome
▪ Heating or cooling room during the required times
o Outputs
▪ Boiler
▪ Air conditioner
o Processing
▪ Check time against the one input and switches on
when that time is reached
▪ Same done to check when to turn off
▪ When on, microprocessor reads temperature from
sensor and compares it with desired temperature
➢ If too low, it will heat up by turning the boiler on
and if it’s too high it will turn the air conditioner on
➢ These will stay on until desired temperature is

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•
When making a computer model, consider:
o What and how data should be collected
o Working of the system in real life.
6.6 Applications in Manufacturing Industries
Robotics
• Robots are used in many areas of manufacturing, from
heavy work right through to delicate operations e.g. car
bodies, welding bodywork, manufacturing of microchips
etc.
• Control of robots is either through embedded
microprocessors or linked to a computer system
• Programming of the robot to do a task is generally done
in two ways:
o The robot is programmed with a sequence of
instructions which allow it to carry out a series of tasks
o Alternatively, a human operator manually carries out a
series of tasks and how each task is done is relayed
back to the robot (embedded processor) or controlling
computer. The sequence of instructions is remembered
so that the robot can automatically carry out each task
identically each time (e.g. assembling parts in a

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• Organising examinations
o Makes sure that the students are enrolled for the right
exams.
o Prints the exam timetables.
o Allots examination rooms and the invigilator.
o Gathers the results and puts them into the student
database.
• Creating timetables and managing teaching
cover/substitution
o Considers the student’s choices, availability of
teachers and rooms, subject clashes and the number of
hours needed for each subject to produce accurate
timetables that can easily be made changes to and
cover with teacher to be substituted.
SCHOOL MANAGEMENT SYSTEMS
ADVANTAGES
DISADVANTAGES
• Absenteeism can be
addressed more easily.
• Parents are kept updated.
• Reduced workload for
teachers.
• They are helpful for the

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6.9 Banking Applications
• Online banking systems rely on the ability to update files
immediately, thus preventing double booking, which
could happen if the system response time was slow
• The use of computer technology has revolutionized how
we do our banking transactions, for example:
o Internet banking
o The use of automated teller machines (ATMs)
o Chip and PIN technology
Automated teller machines (ATMs)
• Automated teller machines (ATMs) are places where
customers can get cash (or carry out certain other
banking activities such as order a statement) using their
credit or debit car
SEQUENCE AT ATM
WHAT GOES ON BEHIND
THE SCENES
Customer puts card into
ATM
Contact is made with
bank’s computer
PIN is entered using the
keypad

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Internet Banking
• Using a username and a password, logging on to a
banking site from your computer or smart phone to
make payments, transfer money, view statements, apply
loans, etc.
TO THE BANK
ADVANTAGES
DISADVANTAGES
• Costs reduced, as some
of the branches can be
closed.
• Fewer employees hence
reduced wage bill.
• Less qualified workers
are accepted which
reduces wage costs.
• Personal services are
reduced, so customers may
move their accounts.
• Loans are easier to lend
face-to-face.
• IT officials are needed to

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6.11 Computers in Libraries
• Many library systems are computer controlled
• They usually involve the use of barcodes on the books
being borrowed and on the borrower’s library card
• The following describes a computerized library system
based on barcodes
• There are two files:
o Book file, containing fields for example: barcode, book
title, name of author etc.
o Borrower’s file, containing fields for example:
borrower’s number, borrower’s name etc.
• When a borrower takes out a book, the book’s code is
scanned
• The book details are then found on book file
• The borrower’s library card barcode is then scanned for
the borrower’s unique number
• The book file is linked to the borrower’s file and both
files are updated to indicate which book has been
borrowed and when it is due back
• The borrower’s file is interrogated daily by the computer
to see which books are overdue for return:
o The computer reads a record from the book file
o It compares the date due back with the current date

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Disadvantages
• They tend to lack common sense in some of the
decision-making processes
• Errors in the knowledge base can lead to incorrect
decisions being made
• It can be expensive to set up in the first place
• Considerable training is necessary to ensure the system
is sued correctly by the operators
Components of an Expert System
User Interface
• This is the only thing that the end user sees
• Allows the user to interact with the system
• Often requires training to operate effectively
Knowledge base
• This is a database designed to allow the complex storage
and retrieval requirements of a computerized
knowledge-based management system (in support of an
expert system)
Inference engine
• This is software that attempts to derive answers from
the knowledge base using a form of reasoning
• It is how expert systems appear to use human-like
reasoning when accessing information from the

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Paying for a meal example
• Waiter inserts card into chip and PIN reader
• Restaurant’s bank contact customer’s bank
• Card is checked to if valid
• If card is stolen or expired, then transaction is
terminated
• Customer enters PIN using keypad
• PIN is read from chip on card and is compared to one
just keyed in
• If they are the same, the transaction can proceed
• Check is then made on whether they have enough funds
• If there are not enough funds available, transaction is
terminated. Otherwise, transaction is authorized
• Authorization code is sent to restaurant
• Price of meal is deducted from customer’s account
• Same amount of money is credited to restaurant’s bank
account
• Receipt is produced as proof of purchase
Internet Shopping
• Online shopping: Shopping over the internet.
TO CUSTOMER
ADVANTAGES
DISADVANTAGES

System Life Cycle
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• RFID in passports:
o The data on the RFID chip is read when the passport is
scanned.
o A photo of you is clicked which is then compared with
the image stored in the RFID chip.
o If the face-recognition passes, some checks are made
in turn to make sure you are eligible to enter the
country, and if you are, the gate opens automatically.
• RFID in contactless payments:
o The embedded chip on credit/debit cards and the
antenna enable customers to wave their card over a
reader at the point of sale terminals to make payments
o Smartphone apps can also be used to make
contactless payments.
6.15 Monitoring & Tracking Systems
• Public monitoring/tracking:
o Ankle monitor: uses RFID chip to give out the person’s
location and other details. It is tamper proof and will
alert authorities if tried to remove.
o Phone call tracking: the service provider tracks the
calls and the exact position from which they were
made
• Worker monitoring/tracking: Workers are

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6.16 Satellite Systems
Global Positioning Systems (GPS)
• Used to determine the exact location of several modes
of transport
• Cars usually refer to GPS as satellite navigation systems
• Satellites surrounding the Earth transmit signals to the
surface
• Computers installed in the mode of transport receive
and interpret these signals
• Knowing their position on the Earth depends on very
accurate timing – atomic clocks are used in the satellites
which are accurate to within a fraction of a second per
day
• Each satellite transmits data indicating its position &
time
• The computer on board the mode of transport calculates
its exact position based on the information from at least
three satellites
Satellite Navigation
• Used to determine the exact location of a car.
o The computers onboard can be used to show
directions to a destination.
Geographic Information Systems (GIS)

PAGE 41 OF 57
• Disadvantages
o People are generally uncomfortable being watched
and may work in a different way
o If workers perform tasks that violate standard
procedures, they may not do this while being watched
Interviews
• Involves a one-to-one question-and-answer session
between the analyst and the employee/customer
• Advantages
o It gives the opportunity to motivate the interviewee
into giving open and honest answers to the analyst’s
questions
o It allows the analyst to probe for more feedback from
the interviewee, as it is easier to extend a question
o It is possible to modify questions as the interview
proceeds and ask questions specific to the interviewee
o It is a good method if the analyst wants to probe
deeply into one specific aspect of the existing system
• Disadvantages
o It can be rather time consuming
o It is relatively expensive, due to the use of the
analyst’s time
o The interviewee cannot remain anonymous

PAGE 42 OF 57
Validation
• Process where data is checked to see if it satisfies certain
criteria when input into a computer, for example to see
if the data falls within accepted boundaries
• Range Check: Checks whether data is within
given/acceptable values.
o E.g. A person’s age should be in range > 0 but < 150
• Length Check: Checks if the input data contains the
required number of characters
o E.g. If a field needs six digits then inputting a five- or
seven-digit number, for example should cause an error
message
• Character/type Check: Checks that the input data does
not contain invalid characters
o E.g. A person’s name should not contain any numbers,
but a person’s height should only contain digits
• Format/picture Check: Checks that data is in a specific
format
o E.g. Date should be in the form dd/mm/yyyy
• Limit Check: Similar to range check except that only one
of the limits (boundaries) is checked
o E.g. Input data must be > 10
• Presence Check: Checks if data is actually present and

PAGE 43 OF 57
• It is a very time-consuming process but the system must
be as perfect as possible before it goes live
• Testing will use many different types of data, which will
fall into one of three categories: normal, extreme or
abnormal
• Let us suppose one of the fields in a database is the date
and this must be in the form dd/mm/yyyy, where each
element of the date must be numeric:
o Normal: this is data which is acceptable/valid and has
an expected (known) outcome, e.g. the month can be
any whole number in the range 1 to 12
o Extreme: this is data at the limits of
acceptability/validity, e.g. the month can be either of
the two end values i.e. 1 or 12
o Abnormal: this is data outside the limits of
acceptability/validity and should be rejected or cause
an error message
o For example, all the following values are not allowed
as inputs for the month:
▪ Negative numbers (e.g. -1, -15)
▪ Any value greater than 12 (e.g. 32, 45)
▪ Letters or other non-numeric data (e.g. July)
▪ Non-integer values (e.g. 3.5, 10.75)

PAGE 44 OF 57
• Advantages
o If the new system fails, only one part of the company
is affected
o It is possible to train staff in one area only, which is
much faster and less costly than parallel running
o The costs are also less than parallel running, since only
one part of the system is being used in the pilot
• Disadvantages
o It is more expensive than direct changeover, since
each pilot scheme needs to be evaluated before the
next stage is introduced
Phased Implementation
• Initially, only part of the new system is introduced
• Only when it proves to work satisfactorily is the next part
introduced, and so on, until old system is fully replaced
• Advantages
o If the latest part fails, it is only necessary to go back in
the system to the point of failure, hence failure is not
disastrous
o It is possible to ensure the system works properly
before expanding
• Disadvantages
o This is more expensive than direct changeover, since it

Safety & Security
PAGE 45 OF 57
User Documentation
• User documentation is designed to help users to learn
how to use the software or system
• This can consist of any of the following:
o the purpose of the system/program/software package
o how to log in/log out
o how to load/run the software
o how to save files
o how to do a search
o how to sort data
o how to do printouts
o how to add, delete or amend records
o screen layouts (input)
o print layouts (output)
o hardware requirements
o software requirements
o sample runs (with test data and results)
o error handling/meaning of errors
o troubleshooting guide/help lines/FAQs
o tutorials
7.6 Evaluation
• Once a system is up and running it is necessary to do
some evaluation and carry out any maintenance, if

PAGE 46 OF 57
8. SAFETY & SECURITY
8.1 Physical Safety
SAFETY HAZARD
WAYS OF ELIMINATING OR
MINIMIZING HAZARD
ELECTROCUTION
FROM SPILLING
DRINKS
• Use a residual circuit breaker
(RCB)
• Check insulation on wires
regularly
• Do not allow drinks near
computers
• Check equipment regularly
TRIPPING OVER
TRAILING WIRES
• Cable ducts- make wires safe
• Cover wires/tuck them away
• Use wireless connections
HEAVY EQUIPMENT
FALLING
• Strong desk/tables to support

PAGE 47 OF 57
Internet Safety
• To keep personal data safe, one must:
o Not give unknown people (on the internet) personal
information or send pictures of oneself to them.
o Maintain privacy settings to control which cookies are
on their computer
o Use learner friendly search engines and websites
recommended by your educational institution, e.g.
Znotes.org
o The website being accessed is from a trusted source,
or has a padlock symbol/ https protocol (s for secure):
Email Safety
• Open emails from known sources, and do not click on an
emails wit hyperlinks without confirming with the sender
of the email. Think before opening an email from an
unknown person, never send any other sensitive
information (picture in school uniform, credit card PIN,
etc.)
• Ask their ISP to eanble email filtering to classfy spam
mails as spam.
Social Media Safety

PAGE 48 OF 57
Biometric Data
• Uses features of the human body unique to every
individual, such as fingerprints, retina, iris, face and voice
recognitions. It is used in authentication techniques as it
is very difficult / impossible to replicate.
ADVANTAGES
DISADVANTAGES
• Usernames and
passwords don’t have to
be remembered
• Almost impossible to
replicate body parts.
• Somebody else can’t
gain access, like with a
stolen card
• They can’t be forgotten,
like a card
• The readers are expensive
• Damages in fingerprints can
deny access
• Some people worry about

PAGE 49 OF 57
Preventing Phishing, Pharming & Smishing
• User education
• Set up anti-malware and anti-spyware software
• Enabling protocols such as SPF and DKIM
• Do not download random .exe (executable file formats),
.php, .bat, .com etc.
• Users should when being redirected to other websites.
• Therefore, technology enables unauthorised users to
gain access to otherwise inaccessible information.
• If a person on the internet is asking for personal
information, or to meet in real life or acting suspicious,
they should be reported to cyber security agencies, or
one’s parents/guardians.
• Websites/pop-ups can be made to mimic legitimate
ones, or seem too good to be true, for e.g.lotrei.net
instead of lottery.com
• Banks and organisations will never ask for a PIN to be
entered on website like this.
Effects of phishing, pharming and Smishing on a user:
• Personal and sensitive information is lost, which can be
used for previously stated purposes.
Moderated & Unmoderated Forums

Audience
PAGE 50 OF 57
• Bogus sites: sites that look exactly like the original sites,
but aren’t.
o They can steal your card details and personal
information when you make purchases.
o Always type in URLs, sometimes links in the mails can
be of bogus sites.
• Phishing, pharming and Smishing:
o They trick you to reveal card and personal details as
responses to messages or mails.
o Open attachments only from trusted sources.
o Install anti-spyware software.
• Hacking into secure sites to obtain the details:
o Encrypting the details will make it of no use to the
hacker.
o Use strong passwords.
o Use firewalls.
• Tapping into wireless networks:
o Always use a password controlled Wi-Fi since it is
relatively hard to tap into a secured Wi-Fi.
*ALL PREVENTION TECHNIQUES WRITTEN HERE ALSO
APPLY FOR THE THREATS IN GENERAL (NOT SPECIFIC TO
CREDIT CARDS) *
Cloud Storage

Communication
PAGE 51 OF 57
9. AUDIENCE
9.1 Audience Appreciation
Knowing Your Audience
• When designing ICT solutions, you must consider
audience
• There are 4 main characteristics of an audience
• Age:
o Can affect audience’s interests in your product
o Large fonts and colours attract children
o More stylish and trendy layout attracts young adults
• Gender
o Design product for a specific gender
o Younger girls are often attracted to pink
o Males generally prefer blue spectrum
• Income
o Knowing this will help in attractive pricing strategies
o Promoting certain products are targeted for people
within a specific range of incomes
• Interests
o Can help with advertising content
o Content that meets the exact description of audience’s
interest is more likely to attract them to your product
Audience Needs

PAGE 52 OF 57
9.2 Legal, Moral, Ethical & Cultural
Appreciation
Copyright Legislation
• A law that protects books, music art and other media
that are written is copyright law
o It is an automatic right and does not need applying for
o The person who owns the rights must be asked before
it can be used again
o Software is a specific thing created and written on a
computer
o Needs to be protected as it is so easy for people to
copy
o This is a way of protecting software from being used
without permission
o Users create a license which determines the terms and
conditions
Copyright Laws
• It is not legal to make a copy of software, then sell it or
give it away to other people
• Software cannot be used on a network unless a network
license has been acquired
• Not legal to use coding from software in your own
software without permission

File Management, Images, Layout, and Styles
PAGE 53 OF 57
Netiquette
• Some of the rules that the netiquette contains is:
o Don’t be abusive
o Don’t send spam
o Be precise
o Check spelling and grammatical errors
o Ensure attachments are not too large
o Don’t use CAPITAL LETTERS to highlight comments
o Don’t plagiarize
o Don’t use too many emoticons
User ID and Password Protection
• Email services are require a user ID to authenticate users
• Passwords should contain alphabets, numbers and
special characters (#,*).
• Email Groups
• Easier to send out multiple mails by grouping them
under one name.
• Companies and organization can group people according
to their target group for marketing purposes.
• Spammers can create email groups by buying addresses
of people from a certain company and send in easier
ways.
• Companies use email groups to set up meetings. Typing

Document Production & Data Manipulation
PAGE 54 OF 57
• Vast amount of information on the internet- easier to
locate than using indices in books
• Information on the internet however may be relevant or
correct, not reliable, inaccurate or even biased- it does
not go through any checking process
• Information overload can make it difficult for the user to
find relevant information
• Ensure use of reliable websites that properly cite all their
sources
• Always look for primary sources of information & form
own conclusions
• Do not quote/use secondary often biased opinions or
gossip
• Do your research
11. FILE MANAGEMENT
11.1 Manage Files Effectively
EXTENSION
NAME
FULL FORM
USED FOR/IN:
.CSS
Cascading Stylesheet

Data Analysis & Website Authoring
PAGE 55 OF 57
15.2 Proofing Techniques
• Verification: checking of data when copied from one
medium to another to prevent errors.
• Verification is also important and is a way of preventing
a difference in data when it’s being transferred from one
system to another. This tries to make sure data entered
is correct, relative to the source.
16. DOCUMENT PRODUCTION
• Widow: A paragraph-ending line that falls at the
beginning of the following page or column, thus
separated from the rest of the text.
• Orphan: A paragraph-opening line that appears by itself
at the bottom of a page or column, thus separated from
the rest of the text.
• Page, section and column breaks are used to ensure that
widows and orphans are not present in a document
(these show poor typography).
• A mail merge document is created in order to create a
standard template and then use it to send documents
personalised (by the computer system) for the
respective recipient of the document
17. DATA MANIPULATION
17.1 Create a Database Structure

PAGE 56 OF 57
• Relative cell referencing is made when the cell reference
is supposed to change when the cell it is referred to in is
changing. It aids more efficient designing of models.
Absolute cell referencing is made when the cell
referenced stays constant when the cell it is referred to
in is changing. This aids the preparation of a model when
a set of data is constantly being referred to throughout
the model. Cell reference or relative cell reference
describes how far away a cell or group of cells is from
some other cell in the same spreadsheet. Basically, the
cell’s address
• A model prepared needs to be tested before being used
to ensure that all results computed are accurate.
• Definitions:
o Cells: A space for data to be entered a table; a box
formed by the intersection of columns and rows
o Rows: Horizontal boxes that divide the table in
segments
o Columns: Vertical boxes that divide the table in
segments
o Sheets: A table of data
o Tabs: A module of a database program that holds the
tables on the computer,

PAGE 57 OF 57
• Definitions:
o Relative file path: A path referring to a file in the same
directory relative to the page the reference is made in.
o Absolute file path: The full path of a file, which is not
relative to anything, whereas relative links only point
to a file or a file path, the browser then redirects the
user to that location on the current site.
▪ Absolute paths always include the domain name of
the website
▪ These should not be used to refer to locally saved
webpages as the computer the webpage is stored on
(the server) is not the same as where the webpage
was developed and thus an absolute file path would
point to the wrong address.
19.3 Use stylesheets
• CSS (cascading stylesheet) is a text-based language
which is attached to webpages to set their format. CSS
files have a “.css” extension
• These should be attached using relative file paths as they
are stored along with the webpage and thus can be
linked relative to them.
• Internal CSS have more preference over Inline CSS
• If several external stylesheets are attached to one web

Types and Components of
Computer Systems

Networks & the Effects of Using
Them

File Management, Images,
Layout, and Styles

Document Production & Data
Manipulation

Data Analysis & Website
Authoring

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