Chapter 2 – Testing Throughout the SDLC
Unit Testing – ISTQB Definition
Last Updated: July 12, 2026 · SoftwareTestPilot QA Team
Official ISTQB Definition
See component testing — a test level that focuses on individual units of code such as functions or classes.
In simple words
Same as component testing: developers verify one small piece of code at a time with fast, automated tests.
Exam tip
ISTQB treats ‘unit testing’ and ‘component testing’ as synonyms — expect the exam to use them interchangeably.
Related terms
- Component TestingTesting the smallest testable pieces of code (a function, class, or module) in isolation, usually by developers.
- Integration TestingAfter units work alone, you plug them together and check the seams — API calls, data hand-offs, contracts.
- Test-Driven DevelopmentRed-green-refactor: write a failing test, make it pass with the simplest code, then clean up.
Practice this term in the ISTQB Mock Test
40 CTFL v4.0 questions, 60-minute timer, instant scoring and chapter-wise breakdown.
Practice in Mock Test