Hardware & Software
Understand the physical components of computers, the programs that control them, and how data flows through digital systems.
Cambridge IGCSE ICT
Component-based
Data conversion
Quick Summary
Every computer is built from hardware (physical parts), runs software (programs), and processes data (either analogue or digital). Understanding how these three work together is the foundation of ICT.
Hardware
Physical components like the CPU, RAM, motherboard, storage, and input/output devices that make up a computer.
Software
Programs and operating systems that control hardware. Can be application (user-chosen) or system (essential).
Data Types
Analogue data is continuous (sound waves), digital is binary (1s and 0s). Computers need digital data to work.
Hardware: The Physical Heart
Hardware is the physical, tangible parts of a computer — the things you can touch. Without hardware, software has nowhere to run.
What is Hardware?
Hardware is the set of physical components that make up a computer system. It includes the CPU, memory, storage devices, and all the input/output devices that let you interact with the machine.
Hardware falls into three main categories:
Internal Components
The CPU: Brain of the Computer
The Central Processing Unit (CPU) is the computer's "brain." It executes instructions, performs calculations, and controls everything else in the computer. Think of it as the decision-maker — every operation on your computer passes through the CPU.
Key fact: The faster the CPU (measured in GHz — gigahertz), the more instructions it can process per second, and the faster your computer responds.
The Motherboard: The Connector
The motherboard is the main circuit board that connects all the important components together. It's like the nervous system of the computer — it allows the CPU, memory, and other components to communicate with each other.
💡 Quick analogy: If the CPU is the brain, the motherboard is the spinal cord that connects the brain to the rest of the body.
Internal Memory: RAM vs. ROM
Internal memory is the computer's "short-term" storage. There are two types, and they work very differently:
| Type |
Speed |
Permanence |
Use |
| RAM (Random Access Memory) |
Very fast |
Lost when powered off |
Temporary working space for programs currently running |
| ROM (Read-Only Memory) |
Slower than RAM |
Permanent |
Stores start-up instructions (BIOS) the CPU needs when turning on |
⚠ Don't confuse these: RAM is temporary and fast (you lose data when you switch off). ROM is permanent but slower (it's read-only, so you can't change it). Think of RAM as a desk you're working at, ROM as a locked instruction manual.
Practice Question
Hardware Components: The Specialists
Practice Question
Software: The Instructions