What is the difference between scripted testing and exploratory testing?

Though exploratory testing and scripted are considered being a part of each other, there is a lot of difference between the two.

The scripted testing is performed by a set of test scripts which can be defined as a set of instructions that are to be performed on the software system or application under the test to test a particular functionality as required.

There are following ways of executing test scripts:

1. Automated testing:
- It can be easily repeated and is faster than manual testing.
- It is very useful when it is required to run the same tests over and over again.
- It is performed as a part of regression testing.
- Automated tests are poorly written and they may break during the execution.
- They only test what has been programmed into them.
- They only ensure that old bugs do not reappear.
- Manual testing and automated testing should be mixed together and used for exploratory testing.

2. Manual testing:
- This is the oldest and the most rigorous forms of testing.
- The test cases are reviewed by the whole testing team before using them.
- The test cases are either created at the basic functionality level or at the scenario level.

3. Short programs or test scripts written in a programming language (C#, C++, expect, TCL, java, Perl, PHP, python, power shell) or a special automated functional GUI test tool (like Borland silk test, HP quick professional test, rational robot etc) can be used to test functionality of a software system or application.

4. Short programs that have been extensively parameterized or data driven testing.

5. Table driven testing or keyword driven testing i.e., using reusable tests created in a table.

CHARACTERISTICS OF SCRIPTED TESTING
- Scripted testing is considered to be as a waste of resources by most of the testers.

- According to them the scripted manual testing inhibits the mind of the tester to use their creativity.

- Also, this testing requires heavy documentation as well as considerable amount of resources to create them.

- They often get out dated since the changes in the system are inevitable.

- Though being so criticized manual scripted testing is used by many organizations.

- The test cases are made repeatable and easy enough for a tester to perform testing with minimum supervision.

- Manual scripted testing is used in contracts where contractual agreement states that written requirements and specifications of the software must be met.

- Scripted test cases are useful where the tests are used as benchmark and have to be executed in the same way, every time.

CHARACTERISTICS OF EXPLORATORY TESTING
- In contrast to scripted testing, exploratory testing is a usual approach to software testing and can be defined as a test designing, test execution and simultaneously learning process.

- Exploratory testing is a kind of software testing that is emphasized and focused up on the responsibility and the personal freedom of the software tester.

- Exploratory testing is a kind of software testing that is emphasized and focused up to optimize the quality and effectiveness of his /her work continually by taking in to consideration mutually supportive activities like test designing, test related learning, test result interpretation and test execution.

- The activities run in parallel to each other.

- Exploratory testing basically heeds to exploiting the creativity of the tester or the programmer.

- During the testing of the software, the tester comes across various new things to learn together with experiencing them.

- Exploratory testing can be thought of as a black box testing methodology or technique instead of thinking of it as an approach to testing that can be used for any type of testing methodology and also at any phase of development of the software system or application.

Who is a good exploratory tester and maintain a balance between scripted and exploratory testing.

Exploratory testing approach relies a lot on the tester alone. The tester actively controls the design of tests as they are performed and uses the information gained to design new and better ideas.
A good exploratory tester should
- have the ability to explain his work.
- he should have the ability to design good tests, execute them and find important problems.
- he should document his ideas and use them in later cycles.
- he should be a careful observer.
- he should be a critical thinker.
- he should have diverse ideas so as to make new test cases and improve existing ones.
- he should remain alert for new opportunities.

Exploratory Testing is advantageous when :
- rapid testing is necessary.
- test case development time is not available.
- need to cover high risk areas with more inputs.
- need to test software with little knowledge about the specifications.
- develop new test cases or improve the existing.

The drawbacks in exploratory testing includes that it is difficult to quantize and a skilled tester is required.
Exploratory testing relies on the tester and the approach he proceeds with. Pure scripted testing does not undergo much change with time and hence the power fades away. In test scenarios, where repeatability of tests is required, automated scripts have an edge over exploratory approach. Hence, it is important to achieve a balance between the two approaches and combine the two to get the best of both.