ISTQB Foundation Level
  • ISTQB CTFL Syllabus 2018 V3.1
  • Author - Magdalena Olak
  • 1. Fundamentals of Testing
    • 1.1. What is Testing?
      • 1.1.1. Typical Objectives of Testing
      • 1.1.2. Testing and Debugging
    • 1.2. Why is Testing Necessary?
      • 1.2.1 Testing’s Contributions to Success
      • 1.2.2 Quality Assurance and Testing
      • 1.2.3 Errors, Defects, and Failures
      • 1.2.4 Defects, Root Causes and Effects
    • 1.3. Seven Testing Principles
    • 1.4. Test Process
      • 1.4.1 Test Process in Context
      • 1.4.2 Test Activities and Tasks
      • 1.4.3 Test Work Products
      • 1.4.4 Traceability between the Test Basis and Test Work Products
    • 1.5. The Psychology of Testing
      • 1.5.1 Human Psychology and Testing
      • 1.5.2 Tester’s and Developer’s Mindsets
  • 2. Testing Throughout the Software Development Lifecycle
    • 2.1. Software Development Lifecycle Models
      • 2.1.1. Software Development and Software Testing
      • 2.1.2. Software Development Lifecycle Models in Context
    • 2.2. Test Levels
      • 2.2.1. Component Testing
      • 2.2.2 Integration Testing
      • 2.2.3. System Testing
      • 2.2.4. Acceptance Testing
    • 2.3. Test Types
      • 2.3.1. Functional Testing
      • 2.3.2. Non-functional Testing
      • 2.3.3. White-box Testing
      • 2.3.4. Change-related Testing
      • 2.3.5. Test Types and Test Levels
    • 2.4. Maintenance Testing
      • 2.4.1 Triggers for Maintenance
      • 2.4.2 Impact Analysis for Maintenance
  • 3 Static Testing
    • 3.1 Static Testing Basics
      • 3.1.1 Work Products that Can Be Examined by Static Testing
      • 3.1.2 Benefits of Static Testing
      • 3.1.3 Differences between Static and Dynamic Testing
    • 3.2 Review Process
      • 3.2.1 Work Product Review Process
      • 3.2.2 Roles and responsibilities in a formal review
      • 3.2.3 Review Types
      • 3.2.4 Applying Review Techniques
      • 3.2.5 Success Factors for Reviews
  • 4 Test Techniques
    • 4.1 Categories of Test Techniques
      • 4.1.1 Categories of Test Techniques and Their Characteristics
    • 4.2 Black-box Test Techniques
      • 4.2.1 Equivalence Partitioning
      • 4.2.2 Boundary Value Analysis
      • 4.2.3 Decision Table Testing
      • 4.2.4 State Transition Testing
      • 4.2.5 Use Case Testing
    • 4.3 White-box Test Techniques
      • 4.3.1 Statement Testing and Coverage
      • 4.3.2 Decision Testing and Coverage
      • 4.3.3 The Value of Statement and Decision Testing
    • 4.4 Experience-based Test Techniques
      • 4.4.1 Error Guessing
      • 4.4.2 Exploratory Testing
      • 4.4.3 Checklist-based Testing
  • 5 Test Management
    • 5.1 Test Organization
      • 5.1.1 Independent Testing
      • 5.1.2 Tasks of a Test Manager and Tester
    • 5.2 Test Planning and Estimation
      • 5.2.1 Purpose and Content of a Test Plan
      • 5.2.2 Test Strategy and Test Approach
      • 5.2.3 Entry Criteria and Exit Criteria (Definition of Ready and Definition of Done)
      • 5.2.4 Test Execution Schedule
      • 5.2.5 Factors Influencing the Test Effort
      • 5.2.6 Test Estimation Techniques
    • 5.3 Test Monitoring and Control
      • 5.3.1 Metrics Used in Testing
      • 5.3.2 Purposes, Contents, and Audiences for Test Reports
    • 5.4 Configuration Management
    • 5.5 Risks and Testing
      • 5.5.1 Definition of Risk
      • 5.5.2 Product and Project Risks
      • 5.5.3 Risk-based Testing and Product Quality
    • 5.6 Defect Management
  • 6 Tool Support for Testing
    • 6.1 Test Tool Considerations
      • 6.1.1 Test Tool Classification
      • 6.1.2 Benefits and Risks of Test Automation
      • 6.1.3 Special Considerations for Test Execution and Test Management Tools
    • 6.2 Effective Use of Tools
      • 6.2.1 Main Principles for Tool Selection
      • 6.2.2 Pilot Projects for Introducing a Tool into an Organization
      • 6.2.3 Success Factors for Tools
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  • 1. Testing shows the presence of defects, not their absence
  • 2. Exhaustive testing is impossible
  • 3. Early testing saves time and money
  • 4. Defects cluster together
  • 5. Beware of the pesticide paradox
  • 6. Testing is context dependent
  • 7. Absence-of-errors is a fallacy

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  1. 1. Fundamentals of Testing

1.3. Seven Testing Principles

A number of testing principles have been suggested over the past 50 years and offer general guidelines common for all testing.

1. Testing shows the presence of defects, not their absence

Testing can show that defects are present, but cannot prove that there are no defects. Testing reduces the probability of undiscovered defects remaining in the software but, even if no defects are found, testing is not a proof of correctness.

2. Exhaustive testing is impossible

Testing everything (all combinations of inputs and preconditions) is not feasible except for trivial cases. Rather than attempting to test exhaustively, risk analysis, test techniques, and priorities should be used to focus test efforts.

3. Early testing saves time and money

To find defects early, both static and dynamic test activities should be started as early as possible in the software development lifecycle. Early testing is sometimes referred to as shift left. Testing early in the software development lifecycle helps reduce or eliminate costly changes (see section 3.1).

4. Defects cluster together

A small number of modules usually contains most of the defects discovered during pre-release testing, or is responsible for most of the operational failures. Predicted defect clusters, and the actual observed defect clusters in test or operation, are an important input into a risk analysis used to focus the test effort (as mentioned in principle 2).

5. Beware of the pesticide paradox

If the same tests are repeated over and over again, eventually these tests no longer find any new defects. To detect new defects, existing tests and test data may need changing, and new tests may need to be written. (Tests are no longer effective at finding defects, just as pesticides are no longer effective at killing insects after a while.) In some cases, such as automated regression testing, the pesticide paradox has a beneficial outcome, which is the relatively low number of regression defects.

6. Testing is context dependent

Testing is done differently in different contexts. For example, safety-critical industrial control software is tested differently from an e-commerce mobile app. As another example, testing in an Agile project is done differently than testing in a sequential software development lifecycle project (see section 2.1).

7. Absence-of-errors is a fallacy

Some organizations expect that testers can run all possible tests and find all possible defects, but principles 2 and 1, respectively, tell us that this is impossible. Further, it is a fallacy (i.e., a mistaken belief) to expect that just finding and fixing a large number of defects will ensure the success of a system. For example, thoroughly testing all specified requirements and fixing all defects found could still produce a system that is difficult to use, that does not fulfill the users’ needs and expectations, or that is inferior compared to other competing systems.

See Myers 2011, Kaner 2002, Weinberg 2008, and Beizer 1990 for examples of these and other testing principles.

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Last updated 4 years ago

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