Exploratory testing - continued

"The plainest definition of exploratory testing is test design and test execution at the same time. Exploratory software testing is a powerful and fun approach to testing. In some situations, it can be orders of magnitude more productive than scripted testing. I haven’t found a tester yet who didn’t, at least unconsciously, perform exploratory testing at one time or another. Yet few of us study this approach, and it doesn’t get much respect in our field. It’s high time we stop the denial, and publicly recognize the exploratory approach for what it is: scientific thinking in real time. Friends, that’s a good thing".
                                                                     James Bach

Exploratory testing seeks to find out how the software actually works, and to ask questions about how it will handle difficult and easy cases. The testing is dependent on the tester's skill of inventing test cases and finding defects. The more the tester knows about the product and different test methods, the better the testing will be.

To further explain, comparison can be made to the antithesis scripted testing, which basically means that test cases are designed in advance, including steps to reproduce and expected results. These tests are later performed by a tester who compares the actual result with the expected.

When performing exploratory testing, there are no exact expected results; it is the tester that decides what will be verified, critically investigating the correctness of the result.

In reality, testing almost always is a combination of exploratory and scripted testing, but with a tendency towards either one, depending on context.

The documentation of exploratory testing ranges from documenting all tests performed to just documenting the bugs. During pair testing, two persons create test cases together; one performs them, and the other documents. Session-based testing is a method specifically designed to make exploratory testing audit-able and measurable on a wider scale.


Benefits and drawbacks

The main advantage of exploratory testing is that less preparation is needed, important bugs are found fast, and is more intellectually stimulating than scripted testing.

Disadvantages are that the tests can't be reviewed in advance (and by that prevent errors in code and test cases), and that it can be difficult to show exactly which tests have been run.

When repeating exploratory tests, they will not be performed in the exact same manner, which can be an advantage if it is important to find new errors; or a disadvantage if it is more important to know that exact things are functional.

- Not advisable for regression testing

- Needs consistent thinking from testers side to come up with various scenarios all the time.

- Can not measure the test coverage.

- Person dependant.

- At times it is proved to be more effective than traditional testing methods.