2025
Computer Applications
Technology
CAT THEORY: GRADE 12 SUMMARIES
Jayden Horn
,Table of Contents:
Table of Contents: ...................................................................................................... 1
Guide to Studying ....................................................................................................... 2
Chapter 1.1: Computers in our everyday lives ........................................................... 3
Chapter 1.2: Hardware Devices ................................................................................. 7
Chapter 1.3: Hardware Recommendations .............................................................. 27
Chapter 1.4: Software .............................................................................................. 36
Chapter 1.5: Systems and Computer Management ................................................. 44
Chapter 2.1 Internet connections and services ........................................................ 53
Chapter 2.2 The dangers of computer crime ............................................................ 62
Chapter 2.3: E-Communications: ............................................................................. 67
Chapter 2.4: The Impact of Technology ................................................................... 74
................................................................................................................................. 78
1|Page
,Guide to Studying
Pages in
Term Modules No. of Pages
Summaries
1 Test 1.1 – 1.4 3 – 43 41
2 (Test if 2.1 – 2.2 53 – 66 14
applicable)
2 Exam 1.1 – 1.4 + 2.1 – 3 – 43 + 53 – 66 55
2.2
3 (Test if 1.5 + 2.3 – 2.4 44 – 52 + 67 – 78 21
applicable)
3 Exam 1.1 – 2.4 3 – 78 76
4 Exam 1.1 – 2.4 3 – 78 76
Foreword:
Dear Matric Student
These summaries only covers Section 1 and 2 of the CAT Study Opportunities
textbook. This is what your Theory paper will primarily consist of. It is also
recommended that you at least read through the other sections of your book before
writing as some questions could also come out of Section 7, as well as various
application questions of your Practical modules.
The way in which you prepare for your Practical exam varies from student to student
and therefore I leave the choice up to you.
As a final piece of advice, it is highly unnecessary to study each and every bullet point,
especially when it comes to uses, advantages, and disadvantages. You can cut some
of these out (not too many though).
Also note that it is important to have a working understanding of the content for
application and scenario questions. This is why I’ve added explanations/examples (out
of the book) to some bullet points. Not for you to study off by heart but instead for you
to gain insight into the work. Do note that these could be asked depending on the
content in question, but it is unlikely. Therefore, I recommend being able to name one
or two examples, whether those are the ones I inserted or your own.
I hope these summaries are of use to you.
Best of luck. Do not lose hope. Hold onto God, and he will provide for you – Psalm 91
& Romans 8:28.
2|Page
,Chapter 1.1: Computers in our everyday lives
Why do we use computers?
• Efficiency
• Accuracy
• Reliability
Efficiency
Computers save:
• Time
• Labour
• Resources
Time:
• Computers work faster than people.
• Computers work in ‘real time’ when tasks need to happen.
Labour
• Reduced labour involved in mentally intensive and repetitive physical tasks.
• Can perform tasks that are dangerous for people.
Resources
• Computers can work more efficiently with resources (e.g. automatically
switching lights off to save electricity)
• Can monitor and limit carbon emissions.
Accuracy
• Repeatable accuracy is essential for e.g. mass production.
• If the software is correct, the computer will be 100% accurate.
Reliability
• Computers don’t get tired, bored, ask for raises, complain or strike.
All this means that:
• Computers are more cost effective in the long run.
Communication
• This, together with efficiency, reliability and accuracy.
− Allows us to eliminate time and distance as business constraints.
3|Page
, • Communicate and share information in many different ways globally.
− Can share information and work on the same information at the same
time.
• Save on communication costs:
− No postage and cheap calls like VoIP.
• Interact socially on a worldwide scale:
− With Social Networking tools like Snapchat, Facebook, etc.
TYPES OF COMPUTER SYSTEMS
When choosing, consider how powerful it must be, what it will be used for, its size,
and software (platforms refer to the types of operating systems used)
Non-portable computers
• Consists of a system unit, screen, mouse, keyboard.
• Large.
• Generally, more powerful than a mobile computer.
Types:
• Desktop computer – costs less for lower specifications
• Server – a powerful computer that provides resources/services to all
computers linked in a network.
What is an entry-level computer?
Cheapest to buy in their range, therefore, low hardware specifications
Portable Computer
• Uses a traditional operating system (e.g. Windows, macOS)
• Portable, i.e. hardware has an all-in-one design (includes e.g. screen,
keyboard, battery)
• Can use it at work and at home.
Description Comments
• Can easily have the
• A device with a screen
same specifications as
size larger than 12’’ or
Laptops / high-end desktops.
13’’
Notebooks • Costs more than a
• Terms can be used
desktop with similar
interchangeably.
specifications.
• Similar to smartphones
• A portable computer
with a touch or pen- • The advantage is that it
Tablet has a larger screen which
sensitive screen.
allows certain apps to
function better.
4|Page
, • Cannot make calls or
send/receive SMS
messages.
• Good for reading and
watching videos.
• Have a longer battery life
than smartphones.
• Appear as normal laptops
• Often have a reversible
but can be used as
(or detachable) screen
tablets.
and a normal
keyboard. • Keyboard is folded
Hybrid behind the screen or
• Screen is touch or pen-
Computer removed.
sensitive. (User
interacts directly with
the screen)
• Often called
‘convertibles’.
• Always on
• A cell phone that
includes an OS and the • Provides instant access
ability to install and run to email, the internet,
Smartphone normal phoning/texting
apps.
• Mostly use touch and additional features
(GPS, games, etc.)
screen interfaces.
• Midway in sizer between
• Smartphone with a
a smartphone and a
screen larger than 5’’
tablet.
• A larger screen size is
Phablet convenient.
• Can make phone calls
like a normal
smartphone.
CATEGORIES OF USERS
1. Personal users: people who do not depend on their computers and do not
spend a lot of time using computers.
Personal users may use a computer for:
• Limited office tasks
• Internet banking
• Email
• Web browsing
• Social networking.
• Skype family/friends
• View/share photos.
5|Page
, • Entertainment
2. SOHO (Small Office Home Office):
• May need entry-level for administration functions like.
− Accounting/billing.
− Databases (e.g. with clients)
− Electronic document archiving
− Planning/scheduling
• May need more powerful computers depending on the jobs. (Architects, etc.)
3. Power users
• Must have top-of-the-range hardware and software.
• For example, hardcore gamers, engineers, architects, etc, need high-end
specifications.
• May use advanced functions of software.
4. Mobile Users
• Mobile users can also fall into any category above.
• Want/need to have technology with them all the time.
• In the past, mobile devices were used for jobs, but now every category above
has and uses mobile technology.
• Choice of mobile technology depends on a person’s needs. Most people use
smartphones or tablets for:
− Browsing the internet and email
− Playing games
− Reading books
− Navigating with GPS
− Taking notes
− Taking photos/videos/recording sound
Convergence: merging or combining multiple technologies into a single,
multipurpose device with features of all combined technologies, like
smartphones/tablets.
6|Page
Computer Applications
Technology
CAT THEORY: GRADE 12 SUMMARIES
Jayden Horn
,Table of Contents:
Table of Contents: ...................................................................................................... 1
Guide to Studying ....................................................................................................... 2
Chapter 1.1: Computers in our everyday lives ........................................................... 3
Chapter 1.2: Hardware Devices ................................................................................. 7
Chapter 1.3: Hardware Recommendations .............................................................. 27
Chapter 1.4: Software .............................................................................................. 36
Chapter 1.5: Systems and Computer Management ................................................. 44
Chapter 2.1 Internet connections and services ........................................................ 53
Chapter 2.2 The dangers of computer crime ............................................................ 62
Chapter 2.3: E-Communications: ............................................................................. 67
Chapter 2.4: The Impact of Technology ................................................................... 74
................................................................................................................................. 78
1|Page
,Guide to Studying
Pages in
Term Modules No. of Pages
Summaries
1 Test 1.1 – 1.4 3 – 43 41
2 (Test if 2.1 – 2.2 53 – 66 14
applicable)
2 Exam 1.1 – 1.4 + 2.1 – 3 – 43 + 53 – 66 55
2.2
3 (Test if 1.5 + 2.3 – 2.4 44 – 52 + 67 – 78 21
applicable)
3 Exam 1.1 – 2.4 3 – 78 76
4 Exam 1.1 – 2.4 3 – 78 76
Foreword:
Dear Matric Student
These summaries only covers Section 1 and 2 of the CAT Study Opportunities
textbook. This is what your Theory paper will primarily consist of. It is also
recommended that you at least read through the other sections of your book before
writing as some questions could also come out of Section 7, as well as various
application questions of your Practical modules.
The way in which you prepare for your Practical exam varies from student to student
and therefore I leave the choice up to you.
As a final piece of advice, it is highly unnecessary to study each and every bullet point,
especially when it comes to uses, advantages, and disadvantages. You can cut some
of these out (not too many though).
Also note that it is important to have a working understanding of the content for
application and scenario questions. This is why I’ve added explanations/examples (out
of the book) to some bullet points. Not for you to study off by heart but instead for you
to gain insight into the work. Do note that these could be asked depending on the
content in question, but it is unlikely. Therefore, I recommend being able to name one
or two examples, whether those are the ones I inserted or your own.
I hope these summaries are of use to you.
Best of luck. Do not lose hope. Hold onto God, and he will provide for you – Psalm 91
& Romans 8:28.
2|Page
,Chapter 1.1: Computers in our everyday lives
Why do we use computers?
• Efficiency
• Accuracy
• Reliability
Efficiency
Computers save:
• Time
• Labour
• Resources
Time:
• Computers work faster than people.
• Computers work in ‘real time’ when tasks need to happen.
Labour
• Reduced labour involved in mentally intensive and repetitive physical tasks.
• Can perform tasks that are dangerous for people.
Resources
• Computers can work more efficiently with resources (e.g. automatically
switching lights off to save electricity)
• Can monitor and limit carbon emissions.
Accuracy
• Repeatable accuracy is essential for e.g. mass production.
• If the software is correct, the computer will be 100% accurate.
Reliability
• Computers don’t get tired, bored, ask for raises, complain or strike.
All this means that:
• Computers are more cost effective in the long run.
Communication
• This, together with efficiency, reliability and accuracy.
− Allows us to eliminate time and distance as business constraints.
3|Page
, • Communicate and share information in many different ways globally.
− Can share information and work on the same information at the same
time.
• Save on communication costs:
− No postage and cheap calls like VoIP.
• Interact socially on a worldwide scale:
− With Social Networking tools like Snapchat, Facebook, etc.
TYPES OF COMPUTER SYSTEMS
When choosing, consider how powerful it must be, what it will be used for, its size,
and software (platforms refer to the types of operating systems used)
Non-portable computers
• Consists of a system unit, screen, mouse, keyboard.
• Large.
• Generally, more powerful than a mobile computer.
Types:
• Desktop computer – costs less for lower specifications
• Server – a powerful computer that provides resources/services to all
computers linked in a network.
What is an entry-level computer?
Cheapest to buy in their range, therefore, low hardware specifications
Portable Computer
• Uses a traditional operating system (e.g. Windows, macOS)
• Portable, i.e. hardware has an all-in-one design (includes e.g. screen,
keyboard, battery)
• Can use it at work and at home.
Description Comments
• Can easily have the
• A device with a screen
same specifications as
size larger than 12’’ or
Laptops / high-end desktops.
13’’
Notebooks • Costs more than a
• Terms can be used
desktop with similar
interchangeably.
specifications.
• Similar to smartphones
• A portable computer
with a touch or pen- • The advantage is that it
Tablet has a larger screen which
sensitive screen.
allows certain apps to
function better.
4|Page
, • Cannot make calls or
send/receive SMS
messages.
• Good for reading and
watching videos.
• Have a longer battery life
than smartphones.
• Appear as normal laptops
• Often have a reversible
but can be used as
(or detachable) screen
tablets.
and a normal
keyboard. • Keyboard is folded
Hybrid behind the screen or
• Screen is touch or pen-
Computer removed.
sensitive. (User
interacts directly with
the screen)
• Often called
‘convertibles’.
• Always on
• A cell phone that
includes an OS and the • Provides instant access
ability to install and run to email, the internet,
Smartphone normal phoning/texting
apps.
• Mostly use touch and additional features
(GPS, games, etc.)
screen interfaces.
• Midway in sizer between
• Smartphone with a
a smartphone and a
screen larger than 5’’
tablet.
• A larger screen size is
Phablet convenient.
• Can make phone calls
like a normal
smartphone.
CATEGORIES OF USERS
1. Personal users: people who do not depend on their computers and do not
spend a lot of time using computers.
Personal users may use a computer for:
• Limited office tasks
• Internet banking
• Web browsing
• Social networking.
• Skype family/friends
• View/share photos.
5|Page
, • Entertainment
2. SOHO (Small Office Home Office):
• May need entry-level for administration functions like.
− Accounting/billing.
− Databases (e.g. with clients)
− Electronic document archiving
− Planning/scheduling
• May need more powerful computers depending on the jobs. (Architects, etc.)
3. Power users
• Must have top-of-the-range hardware and software.
• For example, hardcore gamers, engineers, architects, etc, need high-end
specifications.
• May use advanced functions of software.
4. Mobile Users
• Mobile users can also fall into any category above.
• Want/need to have technology with them all the time.
• In the past, mobile devices were used for jobs, but now every category above
has and uses mobile technology.
• Choice of mobile technology depends on a person’s needs. Most people use
smartphones or tablets for:
− Browsing the internet and email
− Playing games
− Reading books
− Navigating with GPS
− Taking notes
− Taking photos/videos/recording sound
Convergence: merging or combining multiple technologies into a single,
multipurpose device with features of all combined technologies, like
smartphones/tablets.
6|Page
