2.1.1

Computational Thinking

Computational thinking is about approaching problems in a clear, organised way. It focuses on three main ideas: abstraction, decomposition, and algorithmic thinking. If you understand how each one helps break down and refine a problem, you are already covering the key exam skill.

14 exam questions 4 flashcards

What you need to know

  • Define abstraction, decomposition, and algorithmic thinking.
  • Explain how each principle helps solve problems.
  • Apply the three principles to a scenario.

Big Picture

What computational thinking means

Computational thinking is not just for writing programs. It is a way of understanding and solving problems logically.

  • It helps you focus on what matters.
  • It helps large problems feel more manageable.
  • It helps you plan solutions clearly before coding.

Principle 1

Abstraction

Abstraction means ignoring unnecessary detail so you can focus on the important parts of the problem.

A map is a good example of abstraction. It leaves out huge amounts of real-world detail and only keeps the information needed for the journey.

In Computer Science, abstraction makes a problem easier to understand because it reduces distraction and complexity.

Exam wording

A strong answer says abstraction removes unnecessary detail to make the problem easier to solve.

Principle 2

Decomposition

Decomposition means splitting a large problem into smaller, more manageable parts.

If you were designing a game, you might split it into movement, scoring, menus, and collision detection rather than trying to solve everything at once.

  • Each smaller part is easier to understand.
  • Different parts can be designed or tested separately.
  • Decomposition often leads to more organised solutions.

Principle 3

Algorithmic thinking

Algorithmic thinking means planning a solution as a sequence of logical steps.

This is the stage where you think carefully about what the computer or user must do first, next, and last.

It links directly to writing algorithms, flowcharts, and pseudocode later in the course.

High-Value Exam Skill

Applying the three ideas together

Most real exam questions expect you to apply more than one of these ideas at the same time.

  • Abstraction: decide which details can be ignored.
  • Decomposition: split the problem into smaller tasks.
  • Algorithmic thinking: turn the tasks into a logical order of steps.

Revision shortcut

A neat way to remember this topic is simplify, split, and step through.

Key takeaways

  • Computational thinking helps solve problems in a structured way.
  • Abstraction removes unnecessary detail.
  • Decomposition breaks a problem into smaller parts.
  • Algorithmic thinking turns a solution into a sequence of clear steps.

Glossary

Computational thinking
A logical way of understanding and solving problems.
Abstraction
Removing unnecessary detail to focus on what matters.
Decomposition
Breaking a problem into smaller parts.
Algorithmic thinking
Planning a solution as clear, ordered steps.

Test yourself

Common questions