Third-Term Computer Science Exam

Marking Scheme for SSS 1 & 2

1a) Computer software is a set of instructions that tells a computer what to do. It includes all the
programs and applications that enable a computer to perform specific tasks.

1b) The two main categories of computer software are:

i. System Software

Examples:

✓ Operating System (e.g., Windows, macOS, Linux)

✓ Utility Programs (e.g., antivirus software, disk cleanup tools)
✓ Device Drivers (software that controls hardware devices such as printers, scanners,
graphics cards etc.)

ii. Application Software

Examples:

✓ Microsoft Word (word processing)

✓ Google Chrome (web browser)
✓ Adobe Photoshop (image editing)

1c) Computer generation refers to a period marked by a significant technological advancement

in computer hardware, typically characterized by a specific type of electronic components used in
the computer’s construction (e.g. vacuum tubes, transistors, integrated circuits).

1d) Features of the first generation of computers

i. Used vacuum tubes for circuitry.

ii. Were very large and bulky.

iii. Relied mainly on machine language (programmed using binary code).

iv. Consumed a lot of electrical power.

v. Had limited processing speed.

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 vi. Generated a lot of heat, which required cooling systems.

1e) Output devices:

i) Produce music or voice output: Speakers or headphones.

ii) Display text, graphics, video, or animation: Monitor (screen).

iii) Produce a photograph on paper: Printer (specifically a photo printer).

2a) Internal hardware components of a computer system

i. Central Processing Unit (CPU)

Often called the "brain" of the computer; executes instructions and processes data.

ii. Motherboard
The main circuit board that connects and allows communication between all internal
components like CPU, RAM, and storage devices.

iii. Random Access Memory (RAM)

Temporary memory that stores data and instructions currently in use, allowing quick
access for the CPU.

iv. Hard Drive (HDD) or Solid-State Drive (SSD)

Permanent storage devices that store the operating system, software, and files.

v. Power Supply Unit (PSU)

Converts electrical power from an outlet into usable power for the internal components of
the computer.

vi. Graphics Processing Unit (GPU)

Specialized processor responsible for rendering images, video, and animations.

2b) Peripheral devices

Keyboard — Input device for typing letters, numbers, and commands into the computer

Mouse — Pointing device used to control the on-screen cursor and interact with interface
elements .

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Monitor — Output device that displays visual information like text, graphics, and videos

Printer — Output device that produces a physical copy of digital documents on paper

Scanner — Input device for converting printed images or text into digital formats.

External Hard Drive or USB Flash Drive — Input/output device used to store or transfer data
when connected to the computer

2c) Three main categories of printers with one example of each

i. Impact Printers
Example: Dot-matrix printer

ii. Non-impact Printers

Example: Inkjet printer

iii. Laser Printers

Example: Laser printer

2d)

Bit (smallest unit) → Byte (B) → Kilobyte (KB) → Megabyte (MB) → Gigabyte (GB) →
Terabyte (TB) → Exabyte (EB) → Yottabyte (YB) → Zettabyte (ZB).

3a) The above object is a computer mouse. A mouse is a handheld input device used to control the
movement of a cursor on a computer screen. It allows users to interact with the graphical user
interface by clicking, selecting, and executing commands.

3b) Part of a Mouse Functions

i. Left Button Used to select or click on objects or options on the screen.

ii. Scroll Wheel Allows scrolling through documents or web pages.

iii. Right Button Opens context menus or additional options.

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3c) What is an operating system?

An operating system (OS) is software that manages a computer's hardware and software
resources, providing an interface for users to interact with the computer and run applications
efficiently. It handles tasks like file management, memory allocation, and system security.

3d)

i) Windows: this is a popular and widely used graphical operating system developed by
Microsoft. It provides a user-friendly interface with windows, icons, and menus,
making it easy for users to interact with their computers. Windows supports a vast range
of software applications and hardware devices, making it suitable for personal,
business, and gaming use. It is known for its compatibility, ease of use, and extensive
support.
ii) Linux: Linux is an open-source operating system based on the Unix architecture. It is
highly customizable, stable, and secure, making it popular among developers,
programmers, and technical users. Linux is used in servers, desktops, and embedded
systems. Users can modify and distribute their versions of Linux, which is available
through various distributions like Ubuntu, Fedora, and Debian.
iii) MacOS: MacOS is a proprietary operating system designed by Apple Inc. for
Macintosh computers. It features a sleek, intuitive user interface focused on ease of use
and aesthetics. MacOS integrates seamlessly with other Apple devices and services and
is known for its stability, security, and multimedia capabilities, making it ideal for
creative professionals and general users alike.

3e) Input Devices Output Devices

Devices used to send data or commands to Devices used to display or produce data from
the computer. the computer.
Examples: Examples:
i. Keyboard i. Monitor
ii. Mouse ii. Printer
iii. Scanner iii. Speakers
iv. Microphone iv. Headphones
v. Digital Camera v. Projector

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4a) Five key sections of a PC keyboard

i. Alphanumeric keys (letters and numbers)

ii. Function keys (F1 to F12)

iii. Navigation keys (Arrow keys, Home, End, Page Up, Page Down)

iv. Control keys (Ctrl, Alt, Windows/Command, Delete)

v. Numeric keypad (number pad)

4b)

i. Alphanumeric keys: These are the main keys used for typing letters, numbers, and special
characters, forming the core input area for text entry.
ii. Function keys: Located at the top of the keyboard, these keys provide quick access to
specific functions or commands in various software, such as F1 for Help or F5 for Refresh.
iii. Navigation keys: These keys help users move around within documents or web pages -
arrows move the cursor, while Home/End and Page Up/Page Down help jump to specific
areas.
iv. Numeric keypad: Located on the right side, it mimics a calculator layout, enabling fast
numerical data entry and calculations.
4c) Utility software is a type of system software designed to help analyze, configure, optimize, or
maintain a computer. These programs perform specific functions that support the overall
operation of the system, such as cleaning files, managing disks, or backing up data.

4d) Examples of utility programs

i. Disk Cleanup
ii. Antivirus software (e.g., Norton, McAfee)
iii. Disk Defragmenter
iv. Backup Software
v. File Compression tools (e.g., WinRAR, 7-Zip)
vi. System Scanner
vii. Driver Updater
Viii. Data Recovery Software

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4e)
Component Type Description Example
Hardware The physical parts of a computer that you Hard Drive, Monitor,
can see and touch. Keyboard
Software The programs and operating instructions Windows OS, Microsoft
that run on hardware. Word

5a)

iii

5b) Areas where computer technology is applicable

i. Education: Computer technology facilitates e-learning, online courses, digital libraries, and
interactive teaching tools, making education more accessible.

ii. Healthcare: Used for patient records, medical imaging, diagnostic systems, and
telemedicine to improve patient care and streamline operations.

iii. Business and Finance: Employed in accounting, payroll, online banking, e-commerce, and
financial analysis for efficient management and transactions.

iv. Communication: Enables email, social media, video conferencing, and messaging apps,
making global communication faster and easier.

v. Transportation: Used in GPS navigation, traffic management systems, vehicle automation,

and logistics tracking.

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 vi. Manufacturing: Facilitates automation, robotics, computer-aided design (CAD), and
supply chain management, increasing productivity.

vii. Entertainment: Used in gaming, digital movies, music streaming, and virtual reality,
providing diversified entertainment options.

viii. Agriculture: Technologies like drones, precision farming, and data analysis help in crop
monitoring, irrigation, and resource management.

ix. Military and Defense: Computers are used for simulations, surveillance, communication,
and weapon systems.

x. Research and Development: Supports data analysis, simulations, modeling, and scientific
computing in various research fields.

5c)
No RAM (Random Access Memory) ROM (Read-Only Memory)

i. Temporary memory that stores data and Permanent memory that stores essential
instructions currently in use. instructions for booting the system.

ii. Volatile - data is lost when power is Non-volatile - retains data even when power
turned off. is off.

iii. Read and write; data can be modified. Read-only; data is pre-programmed and
cannot be easily modified.

iv. Used for running applications and the Used to store firmware, BIOS, or system
operating system during operation. startup instructions.

v. Faster access speeds. Generally slower compared to RAM.

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6a)

6b)

i. Keyboard - Input device for typing letters, numbers, and commands into the computer
ii. Mouse - Pointing device used to control the on-screen cursor and interact with interface
elements.
iii. System Unit – It is the main physical case or enclosure of a computer that contains the
essential internal hardware components necessary for the computer to operate.
iv. Monitor - Output device that displays visual information like text, graphics, and videos
v. Speaker - A speaker is an output device that converts electrical signals into sound, allowing
users to hear audio from the computer, such as music, system sounds, or voice in video
calls.

6c) Hardware devices that are found inside component iii (system unit):

i. Central Processing Unit (CPU)

ii. Motherboard
iii. Random Access Memory (RAM)
iv. Hard Drive (HDD) or Solid-State Drive (SSD)
v. Power Supply Unit (PSU)
vi. Graphics Card (GPU)

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6d) Booting is the process of starting a computer and loading the operating system into memory
so that the system becomes operational and ready for use.

6e)

No Cold Booting Warm Booting

i Starting the computer from a Restarting the computer without turning off
completely powered-off state. power, usually via the restart command.

ii Powering on, POST (Power-On Self- Rebooting the system while it is already
Test), then loading the OS. powered on, often via the operating system.

iii Turning on your computer after it has Click "Restart" in the OS or pressing Ctrl + Alt
been shut down. + Delete.