Know and understand applications software provides the services that the user requires to solve a task

Published by Patrick Mutisya · 14 days ago

ICT 0417 – Types and Components of Computer Systems

ICT 0417 – Types and Components of Computer Systems

Learning Objective

Know and understand how application software provides the services that the user requires to solve a task.

1. Overview of Computer Systems

A computer system consists of hardware, system software and application software. The hardware provides the physical components, system software manages resources, and application software enables users to perform specific tasks.

2. Types of Computer Systems

Computer systems can be classified according to size, purpose and architecture.

  • Based on size: Supercomputer, Mainframe, Minicomputer, Microcomputer (PC), Mobile devices.

  • Based on purpose: General‑purpose, Special‑purpose (e.g., embedded systems, real‑time systems).

  • Based on architecture: Centralised, Distributed, Client‑server, Cloud‑based.

3. Components of a Computer System

ComponentFunction
Central Processing Unit (CPU)Executes instructions; performs calculations and logical operations.
MemoryStores data and programs temporarily (RAM) and permanently (ROM, storage).
Input DevicesAllow users to enter data (keyboard, mouse, scanner, microphone).
Output DevicesPresent processed information (monitor, printer, speakers).
Storage DevicesLong‑term data retention (hard disk, SSD, USB flash drive, optical disc).
MotherboardProvides the circuitry for communication between components.
Power SupplyConverts mains electricity to low‑voltage DC power for components.
Network InterfaceEnables communication with other computers (Ethernet, Wi‑Fi).

4. Application Software

Application software is designed to help the user perform specific tasks. It sits on top of system software and uses the hardware resources to deliver services.

4.1 Categories of Application Software

  1. Productivity Software – word processors, spreadsheets, presentation tools.

  2. Database Management Systems (DBMS) – store, retrieve and manipulate data.

  3. Multimedia Software – image editors, video editors, audio players.

  4. Communication Software – email clients, web browsers, instant messaging.

  5. Educational Software – tutorials, simulations, e‑learning platforms.

  6. Special‑purpose Software – accounting packages, CAD, medical imaging.

4.2 How Application Software Provides Services

Application software translates user requirements into computer actions. The typical process is:

  1. User identifies a task (e.g., create a report).

  2. Selects appropriate application (e.g., word processor).

  3. Enters data using input devices.

  4. Application processes data using the CPU and memory.

  5. Results are displayed via output devices or stored for later use.

4.3 Example: Solving a Task with a Spreadsheet

A common task is calculating monthly expenses.

  • Open the spreadsheet application.

  • Enter categories (Rent, Utilities, Food, etc.) in column A.

  • Enter amounts in column B.

  • Use a formula to sum the total: =SUM(B2:B10).

  • Generate a chart to visualise spending.

4.4 Benefits of Application Software

  • Increases productivity by automating repetitive tasks.

  • Improves accuracy through built‑in calculations and validation.

  • Facilitates communication and data sharing.

  • Provides specialised tools for specific industries.

5. Summary

Understanding the types and components of computer systems helps learners appreciate how application software leverages hardware and system software to deliver the services required to solve real‑world tasks.

Suggested diagram: Layered model showing hardware → system software → application software → user tasks.