COMPUTER FUNDAMENTALS Lesson Note
This SS1 DIGITAL TECHNOLOGY lesson note covers COMPUTER FUNDAMENTALS for First Term, Week 2.
Learning Objectives
- By the end of the lesson, students should be able to:
- Define a computer.
- Explain the basic functions of a computer.
- Identify the major characteristics of computers.
- Identify the major components of a computer system.
- Explain the difference between hardware and software.
- Identify different types of computers.
- Describe common input, output, processing and storage devices.
- Explain the basic computer operations.
- State the importance of computers in everyday life.
- Identify some limitations of computers.
Lesson Note
A. MEANING OF A COMPUTER
A computer is an electronic device that accepts data as input, processes the data according to a set of instructions, stores data and information, and produces useful information as output.
In simple terms, a computer is a machine that receives data, processes it, stores it and gives out information.
B. BASIC COMPUTER PROCESS
Input → Processing → Output → Storage
For example, when a student enters marks into a computer:
Input: The marks are entered using the keyboard.
Processing: The computer calculates the total or average.
Output: The result is displayed on the monitor.
Storage: The result can be saved for future use.
C. DATA AND INFORMATION
DATA
Data refers to raw facts and figures that have not yet been processed into meaningful information.
Examples include: 25, 40, “John”, 15/09/2026, 75, 80, 65
INFORMATION
Information is processed and organized data that is meaningful and useful to the user.
For example, if the marks 75, 80 and 65 are processed to calculate an average of 73.3, the average is the information.
D. DIFFERENCE BETWEEN DATA AND INFORMATION
Data. Information
Raw facts and figures Processed and meaningful data
May not be immediately useful Useful for decision-making
Has not been processed Has been processed
Example: 70, 80, 90 Example: Average = 80
E. BASIC FUNCTIONS OF A COMPUTER
A computer performs four major basic functions:
1. INPUT
Input is the process of entering data and instructions into a computer.
Examples of input devices include: Keyboard, Mouse, Scanner, Microphone, Webcam and Touchscreen
2. PROCESSING
Processing is the manipulation of input data according to instructions to produce useful results.
The Central Processing Unit (CPU) is mainly responsible for processing in a computer.
3. OUTPUT
Output is the result produced after data has been processed.
Examples of output devices include: Monitor, Printer, Speakers, Projector and Headphones
4. STORAGE
Storage involves keeping data, instructions and information for future use.
Examples of storage devices include: Hard disk drive (HDD), Solid-state drive (SSD), USB flash drive, Memory card and Optical disc
F. CHARACTERISTICS OF COMPUTERS
Computers have several important characteristics.
1. Speed
Computers can perform millions or billions of operations in a very short period.
2. Accuracy
When given correct data and instructions, computers can produce highly accurate results.
3. Storage Capacity
Computers can store large amounts of data and information.
4. Diligence
A computer does not become tired or bored when repeatedly performing the same task.
5. Automation
Once properly programmed and instructed, a computer can perform tasks automatically.
6. Versatility
Computers can perform many different types of tasks, such as typing, calculations, communication, designing and entertainment.
7. Reliability
Computers can perform tasks repeatedly and consistently when properly maintained.
8. Multitasking
Modern computers can run several programs or perform several tasks at the same time.
G. COMPONENTS OF A COMPUTER SYSTEM
A computer system consists of several components that work together.
The major components include:
Hardware
Software
Data
Users
Procedures
1. COMPUTER HARDWARE
Hardware refers to the physical parts of a computer that can be seen and touched.
Examples include: Monitor, Keyboard, Mouse, System unit, Printer, Speakers, Hard drive, Motherboard and RAM
MAJOR CATEGORIES OF HARDWARE
i. Input Hardware
Used to enter data into a computer.
Examples: Keyboard, Mouse, Scanner, Microphone and Webcam
ii. Processing Hardware
Used to process data.
The main example is the Central Processing Unit (CPU).
III OUTPUT HARDWARE
Used to present processed information to the user.
Examples: Monitor, Printer, Speakers and Projector
IV. STORAGE HARDWARE
Used to store data and information.
Examples: HDD, SSD, USB flash drive and Memory card
2. COMPUTER SOFTWARE
Software refers to programs and instructions that tell computer hardware what to do.
Software cannot normally be physically touched like hardware.
TYPES OF SOFTWARE
i. System Software
System software controls and manages computer hardware and provides a platform for application programs.
Examples: ,Windows, Linux, macOS and Android
The operating system is an important type of system software.
II. APPLICATION SOFTWARE
Application software is designed to help users perform specific tasks.
Examples include: Word processors, Spreadsheet applications, Presentation software, Web browsers, Graphics applications and Media players
H. HARDWARE AND SOFTWARE RELATIONSHIP
Hardware and software depend on each other.
Hardware provides the physical equipment, while software provides the instructions that control the equipment.
For example, a keyboard is hardware, while the program that receives and processes what is typed is software.
Without software, computer hardware cannot perform useful tasks effectively. Likewise, software requires hardware on which it can operate.
I. TYPES OF COMPUTER Computers can be classified according to size, processing capacity, purpose and usage.
1. Desktop Computer
A desktop computer is designed to remain in a fixed location, usually on a desk.
Uses: office work, education, business and home computing.
2. Laptop Computer
A laptop is a portable computer with a built-in screen, keyboard, battery and other components.
Uses: education, business, communication and entertainment.
3. Tablet Computer
A tablet is a portable computer that is mainly operated through a touchscreen.
4. Smartphone
A smartphone is a mobile digital device that combines communication and computing functions.
5. Mainframe Computer
A mainframe is a powerful computer designed to process large amounts of data and support many users or applications.
It is commonly used by large organizations.
6. Supercomputer
A supercomputer is an extremely powerful computer designed to perform very complex calculations at very high speeds.
It can be used for scientific research, weather modelling and other computationally demanding tasks.
J. BASIC PARTS OF A DESKTOP COMPUTER
A typical desktop computer may have the following parts:
i. Monitor
The monitor displays text, pictures, videos and other information.
ii. Keyboard
The keyboard is used mainly for entering text, numbers and commands.
iii. Mouse
The mouse is a pointing device used to select, open, move and interact with items on the screen.
iv. System Unit
The system unit contains important internal components such as the motherboard, CPU, RAM and storage devices.
v. Speakers
Speakers produce sound from the computer.
vi. Printer
A printer produces a physical copy of digital information on paper.
vii. The Central Processing Unit (CPU)
The Central Processing Unit (CPU) is a major processing component of a computer. It executes instructions and performs calculations and logical operations.
The CPU is commonly described as the “brain” of the computer, although this is only an analogy.
Major parts associated with the CPU include:
a. Arithmetic and Logic Unit (ALU)
The ALU performs:
*Arithmetic operations such as addition, subtraction, multiplication and division.
*Logical comparisons such as greater than, less than and equal to.
b. Control Unit (CU)
The Control Unit coordinates the activities of the computer by directing the movement and processing of instructions and data.
c. Registers
Registers are very small, fast storage locations within the CPU used to temporarily hold data, instructions or intermediate results during processing.
K. IMPORTANCE OF COMPUTERS
Computers are important in many areas of life.
Education
They are used for:
*Teaching and learning
*Research
*Preparing documents
*Online learning
*Computer-based examinations
Business
Computers are used for:
*Accounting
*Record keeping
*Stock management
*Communication
*Data analysis
Banking
They support:
*Electronic transactions
*ATM services
*Account management
*Online banking
Healthcare
Computers are used for:
*Patient records
*Medical research
*Laboratory work
*Medical imaging
*Hospital administration
Communication
*/Computers support:
*Video conferencing
*Messaging
*Social networking
*Internet communication
Entertainment
They are used for:
*Music
*Movies
*Games
*Digital photography
*Video editing
L. LIMITATIONS OF COMPUTERS
Despite their many advantages, computers have limitations.
1. Computers cannot think like humans: They follow instructions and processes provided by people and software.
2. They depend on electricity or power: Most computers require a source of power to operate.
3. Incorrect input can produce incorrect results: A computer may produce wrong results when given incorrect data or instructions.
4. Security risks: Computers can be affected by malware and other cyber threats.
5. Maintenance is required: Hardware and software may need repairs, updates and maintenance.
6. Cost: Purchasing and maintaining some computer systems can be expensive.
M. BASIC COMPUTER OPERATIONS
The basic operations of a computer include:
1. Starting the computer: Turning on the computer and allowing it to load the operating system.
2. Logging in: Entering the required user credentials where applicable.
3. Opening applications: Selecting programs needed for a task.
4. Creating information: Entering text, numbers or other data.
5. Saving files: Storing work for future use.
6. Retrieving files: Opening previously saved information.
7. Printing: Producing a physical copy of information.
8. Shutting down: Properly closing applications and turning off the computer.
SUMMARY
A computer is an electronic device that accepts data, processes it, produces information and stores data or information for future use. The four basic functions of a computer are input, processing, output and storage.
Computer systems consist of hardware, software, data, users and procedures. Computers are available in different forms, including desktops, laptops, tablets, smartphones, mainframes and supercomputers.
Computers are widely used in education, business, banking, healthcare, communication, transportation and entertainment. However, they also have limitations and must be used responsibly and maintained properly.
Evaluation
OBJECTIVE QUESTIONS
Choose the correct answer from options A–D.
1. A computer is an electronic device that accepts data, processes it and produces _____.
A. Electricity
B. Information
C. Noise
D. Paper
2. Which of the following is the first stage in the basic computer process?
A. Output
B. Storage
C. Input
D. Processing
3. Raw facts and figures that have not been processed are called _____.
A. Information
B. Data
C. Software
D. Instructions
4. Which component is mainly responsible for processing instructions in a computer?
A. Keyboard
B. Monitor
C. CPU
D. Printer
5. Which of the following is an input device?
A. Monitor
B. Printer
C. Keyboard
D. Speaker
6. Which of the following is an output device?
A. Mouse
B. Scanner
C. Keyboard
D. Monitor
7. The physical parts of a computer are called _____.
A. Software
B. Hardware
C. Data
D. Programs
8. Which of the following is system software?
A. Windows
B. Keyboard
C. Printer
D. Mouse
9. Which type of computer is designed to be portable and can be carried from one place to another?
A. Laptop
B. Mainframe
C. Supercomputer
D. Desktop
10. Which part of the CPU performs arithmetic and logical operations?
A. Control Unit
B. Arithmetic and Logic Unit
C. Monitor
D. Storage Unit
Theory Questions
1a. Define a computer and explain the four basic functions of a computer.
1b. Differentiate between data and information, giving two examples of each.
2a. What is computer hardware? List five examples of computer hardware.
2b. Explain the difference between system software and application software, giving two examples of each.
2c. State five characteristics and five uses of computers.