Software that hasn't been tested isn't trustworthy, no matter how clever the code. This chapter is about proving software works and keeping it working: why we test in the first place, the test pyramid that shapes a healthy test suite, the practice of writing tests first, the real work of quality assurance, and how a bug travels from report to fix.
5 topics
Every chapter so far has helped build software well. This one asks the blunt question that decides whether any of it matters: does it actually work? Testing is how teams answer that with confidence — and it turns out the goal isn't what most beginners think.
Five topics. First, why we test at all — and why the honest goal is confidence, not proof. Then the test pyramid, the standard shape of a good test suite. Then writing tests before the code, in TDD and BDD. Then the human side: manual testing, exploratory testing, and what QA really does. And finally the lifecycle a bug travels, from report to triage to fixed.