Experience-based Test Techniques

Exploratory Testing 

In exploratory testing, informal (not pre-defined) tests are designed, executed, logged, and evaluated
dynamically during test execution. The test results are used to learn more about the component or
system, and to create tests for the areas that may need more testing.
Exploratory testing is sometimes conducted using session-based testing to structure the activity. In
session-based testing, exploratory testing is conducted within a defined time-box, and the tester uses a
test charter containing test objectives to guide the testing. The tester may use test session sheets to
document the steps followed and the discoveries made.

Exploratory testing is most useful when there are few or inadequate specifications or significant time
pressure on testing. Exploratory testing is also useful to complement other more formal testing
techniques.
Exploratory testing is strongly associated with reactive test strategies. Exploratory testing can incorporate the use of other black-box, white-box, and experience-based techniques.

Checklist-based Testing

In checklist-based testing, testers design, implement, and execute tests to cover test conditions found in a checklist. As part of analysis, testers create a new checklist or expand an existing checklist, but testers
may also use an existing checklist without modification. Such checklists can be built based on experience, knowledge about what is important for the user, or an understanding of why and how
software fails.

Checklists can be created to support various test types, including functional and non-functional testing. In the absence of detailed test cases, checklist-based testing can provide guidelines and a degree of
consistency. As these are high-level lists, some variability in the actual testing is likely to occur, resulting in potentially greater coverage but less repeatability.

Error Guessing

Error guessing is a technique used to anticipate the occurrence of errors, defects, and failures, based on
the tester’s knowledge, including:

• How the application has worked in the past
• What kind of errors tend to be made
• Failures that have occurred in other applications

A methodical approach to the error guessing technique is to create a list of possible errors, defects, and
failures, and design tests that will expose those failures and the defects that caused them. These error,
defect, failure lists can be built based on experience, defect and failure data, or from common knowledge about why software fails.