ISTQB Foundation Quick Reference

7 Testing Principles

1. Testing shows presence of defects, not absence
2. Exhaustive testing is impossible
3. Early testing saves time and money
4. Defects cluster together
5. Pesticide paradox (same tests → fewer bugs found)
6. Testing is context dependent
7. Absence-of-errors fallacy

Test Levels

• Unit → Individual components
• Integration → Interfaces between components
• System → Complete system behavior
• Acceptance → Business requirements met?

Test Types

• Functional — Does it do what it should?
• Non-functional — Performance, security, usability
• Structural — Code coverage, paths
• Regression — Did changes break anything?

Test Design Techniques

• Equivalence Partitioning — Divide inputs into classes
• Boundary Value Analysis — Test at edges of ranges
• Decision Table — All combinations of conditions
• State Transition — Test state changes

Key Terms

• Defect — Flaw in code/docs that may cause failure
• Error — Human mistake that produces a defect
• Failure — Software doesn't do what it should
• Test Oracle — How you know if output is correct
• Test Basis — Docs used to derive test cases