Hardware, Software, Data & Information

Before anything else, IT theory needs a shared vocabulary. This subtopic sets up the four words you'll use in every answer from here on: hardware, software, data, and information.

A computer system is really just a combination of hardware and software working together to turn data into information.

Hardware: The physical, tangible parts of a computer system — anything you can actually touch: the CPU, RAM, keyboard, monitor, hard drive.
Software: The set of instructions (programs) that tell the hardware what to do. You cannot physically touch software — only the media it's stored on.
Data: Raw, unprocessed facts and figures with no context — e.g. the number 37, or the string 'Smith'. On its own it means very little.
Information: Data that has been processed, organised and given context so that it becomes meaningful and useful — e.g. 'The average temperature this week was 37°C.'

An ICT system (Information and Communication Technology system) combines hardware, software, data, procedures and people to collect, process, store and communicate information.

The generic model of a computer is the IPO model — every computer, no matter how complex, can be described this way:

The IPO model, extended to IPOS with an optional Storage stage.

Stage	What happens	Examples
Input	Data enters the system	Keyboard, mouse, scanner, microphone, sensor
Processing	Data is manipulated/transformed by the CPU	Calculations, sorting, comparisons
Output	The processed result (information) leaves the system	Monitor, printer, speaker

Many exam questions extend this to IPOS (Input – Processing – Output – Storage), since most systems also need to save data for later.

Advantages of using computers: speed, accuracy, consistency, storage capacity, ability to automate repetitive tasks, communication over long distances.
Disadvantages: cost (hardware, software, maintenance, training), reliance on electricity, security/privacy risks, potential for job losses through automation, health issues from overuse (RSI, eye strain).

Example

Data: 20, 22, 19, 25, 21 (five numbers with no context). Information: 'The average daily temperature this week was 21.4°C' — the same numbers, processed and given meaning.

💡 Exam Tip

Exam trap: students often say 'data is information that hasn't been processed' — rather define each term independently and then explain the relationship, since IEB memos give marks for both halves.