1. Introduction to Computers
A computer is an electronic device that accepts data as input, processes it according to instructions,
and gives meaningful output. Computers are capable of storing information, executing programs, and
performing arithmetic and logical operations.
Characteristics of a Computer
- Speed: Performs millions of operations per second.
- Accuracy: Produces error-free results when input is correct.
- Storage: Stores large volumes of data.
- Diligence: Does not get tired or bored.
- Automation: Works automatically once programmed.
- Versatility: Can perform different types of tasks.
Basic Terms
- Data: Raw facts (numbers, text, images).
- Information: Processed data that is meaningful.
- Hardware: Physical parts of the computer.
- Software: Instructions/programs that run on the computer.
- User: The person who operates the computer.
2. Components of a Computer System
A. Hardware
Hardware refers to physical + tangible components of the computer.
(i) Input Devices
- Keyboard
- Mouse
- Scanner
- Microphone
- Touchscreen
- Barcode Reader
(ii) Output Devices
- Monitor
- Printer
- Projector
- Speakers
- Plotter
(iii) Storage Devices
- Hard Disk Drive (HDD)
- Solid State Drive (SSD)
- Flash Drives
- Memory Cards
- CD/DVD
(iv) Central Processing Unit (CPU)
The CPU is the “brain” of the computer and consists of:
- ALU: Performs arithmetic and logical operations.
- CU: Controls all operations in the system.
- Registers: Small high-speed storage areas.
(v) Memory
- RAM: Temporary working memory.
- ROM: Permanent memory containing boot instructions.
- Cache: High-speed memory close to the CPU.
3. Software
A. System Software
Software that controls hardware and provides the environment for other programs.
- Operating Systems (Windows, Linux, macOS)
- Utility Programs (antivirus, file managers)
- Firmware
B. Application Software
- Microsoft Office (Word, Excel)
- Scratch, Python, Raptor (for Cameroon ICT curriculum)
- Browsers (Chrome, Firefox)
- Media Players
- Mobile Apps
4. Types of Computers
- Supercomputers: Extremely powerful.
- Mainframes: Used by banks, airlines.
- Minicomputers: Mid-range systems.
- Microcomputers: Laptops, desktops.
- Embedded Systems: Found in cars, phones.
5. Computer Networks
Definition
A network is a group of computers linked to share data and resources.
Types of Networks
- LAN: Local Area Network (school, office)
- WAN: Wide Area Network (MTN, CAMTEL)
- MAN: Metropolitan Area Network
- WLAN: Wireless LAN
Network Devices
- Router
- Switch
- Modem
- Access Point
- Network Cables
6. Internet & Web Technologies
Internet Terms
- WWW: World Wide Web
- Browser: Program used to access websites
- URL: Address of a webpage
- Search Engine: Google, Bing, Yandex
- Email: Electronic messaging service
Uses of the Internet
- E-learning (GCE prep sites)
- Communication
- E-commerce
- Banking & Mobile Money
- Research & project work
7. Computer Security
- Use of antivirus
- Firewalls
- Passwords & authentication
- Software updates
- Safe browsing practices
8. Computer Ethics
- Avoid piracy
- Respect privacy
- Do not spread malware
- Use computers responsibly in school & society
Note: These notes follow the Cameroon Computer science syllabus (Forms 1–5 & Lower Sixth fundamentals).