GCSERevise
AQASpec 3.1Foundation & Higher~35 min

Algorithms and Computational Thinking

Computer Science · Topic revision workspace

Topic progress0%

Read the notes, score 80% and know 75% of the cards.

Topic overview

What you need to know

Algorithms solve problems through precise, finite steps. Learn decomposition, abstraction, searching, sorting, trace tables and how to compare efficiency.

Exam tip

Trace the exact algorithm given before relying on memory. Show every changed variable and output in the table.

Revision notes

Core ideas

Secure these ideas first. Say each definition in your own words, then connect it to the topic overview.

  • Algorithm: A finite sequence of unambiguous steps that solves a problem.
  • Decomposition: Breaking a complex problem into smaller manageable parts.
  • Abstraction: Removing unnecessary detail so the important features are easier to work with.

Revision notes

Apply it in the exam

The exam will rarely ask for an isolated definition. Practise selecting the right idea and using it as part of a complete explanation or method.

  • Binary search: A search of sorted data that repeatedly halves the remaining search area.
  • Merge sort: A divide-and-conquer sort that splits data, sorts parts and merges them.
  • Trace table: A table used to record variable values and outputs as an algorithm executes.

Core knowledge

Key facts for Algorithms and Computational Thinking

1

Algorithm

A finite sequence of unambiguous steps that solves a problem.

2

Decomposition

Breaking a complex problem into smaller manageable parts.

3

Abstraction

Removing unnecessary detail so the important features are easier to work with.

4

Binary search

A search of sorted data that repeatedly halves the remaining search area.

5

Merge sort

A divide-and-conquer sort that splits data, sorts parts and merges them.

6

Trace table

A table used to record variable values and outputs as an algorithm executes.

Active recall

Close the notes and answer these

  1. 1.Without looking, explain algorithm and give one example or consequence.
  2. 2.Without looking, explain decomposition and give one example or consequence.
  3. 3.Without looking, explain abstraction and give one example or consequence.
  4. 4.Without looking, explain binary search and give one example or consequence.

Content reviewed 23 July 2026 against the current linked specification.

Finished learning?

Mark the notes complete, then test what you can recall.

Official AQA specification
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