Software testing is an investigation conducted to provide stakeholders with information about the quality of the product or service under test.^[1] Software testing can also provide an objective, independent view of the software to allow the business to appreciate and understand the risks of software implementation. Test techniques include, but are not limited to, the process of executing a program or application with the intent of finding software bugs (errors or other defects).

Software testing can be stated as the process of validating and verifying that a software program/application/product:

1. meets the requirements that guided its design and development;
2. works as expected;
3. can be implemented with the same characteristics.
4. satisfies the needs of stakeholders

Software testing, depending on the testing method employed, can be implemented at any time in the development process. However, most of the test effort traditionally occurs after the requirements have been defined and the coding process has been completed. Although in the Agile approaches most of the test effort is, conversely, on-going. As such, the methodology of the test is governed by the software development methodology adopted.

Different software development models will focus the test effort at different points in the development process. Newer development models, such as Agile, often employ test driven development and place an increased portion of the testing in the hands of the developer, before it reaches a formal team of testers. In a more traditional model, most of the test execution occurs after the requirements have been defined and the coding process has been completed.

Overview[link]

Testing can never completely identify all the defects within software.^[2] Instead, it furnishes a criticism or comparison that compares the state and behavior of the product against oracles—principles or mechanisms by which someone might recognize a problem. These oracles may include (but are not limited to) specifications, contracts,^[3] comparable products, past versions of the same product, inferences about intended or expected purpose, user or customer expectations, relevant standards, applicable laws, or other criteria.

Every software product has a target audience. For example, the audience for video game software is completely different from banking software. Therefore, when an organization develops or otherwise invests in a software product, it can assess whether the software product will be acceptable to its end users, its target audience, its purchasers, and other stakeholders. Software testing is the process of attempting to make this assessment.

A study conducted by NIST in 2002 reports that software bugs cost the U.S. economy $59.5 billion annually. More than a third of this cost could be avoided if better software testing was performed.^[4]

History[link]

The separation of debugging from testing was initially introduced by Glenford J. Myers in 1979.^[5] Although his attention was on breakage testing ("a successful test is one that finds a bug"^[5][6]) it illustrated the desire of the software engineering community to separate fundamental development activities, such as debugging, from that of verification. Dave Gelperin and William C. Hetzel classified in 1988 the phases and goals in software testing in the following stages:^[7]

• Until 1956 - Debugging oriented^[8]
• 1957–1978 - Demonstration oriented^[9]
• 1979–1982 - Destruction oriented^[10]
• 1983–1987 - Evaluation oriented^[11]
• 1988–2000 - Prevention oriented^[12]

Software testing topics[link]

Scope[link]

A primary purpose of testing is to detect software failures so that defects may be discovered and corrected. Testing cannot establish that a product functions properly under all conditions but can only establish that it does not function properly under specific conditions.^[13] The scope of software testing often includes examination of code as well as execution of that code in various environments and conditions as well as examining the aspects of code: does it do what it is supposed to do and do what it needs to do. In the current culture of software development, a testing organization may be separate from the development team. There are various roles for testing team members. Information derived from software testing may be used to correct the process by which software is developed.^[14]

Functional vs non-functional testing[link]

Functional testing refers to activities that verify a specific action or function of the code. These are usually found in the code requirements documentation, although some development methodologies work from use cases or user stories. Functional tests tend to answer the question of "can the user do this" or "does this particular feature work."

Non-functional testing refers to aspects of the software that may not be related to a specific function or user action, such as scalability or other performance, behavior under certain constraints, or security. Testing will determine the flake point, the point at which extremes of scalability or performance leads to unstable execution. Non-functional requirements tend to be those that reflect the quality of the product, particularly in the context of the suitability perspective of its users.

Defects and failures[link]

Not all software defects are caused by coding errors. One common source of expensive defects is caused by requirement gaps, e.g., unrecognized requirements, that result in errors of omission by the program designer.^[15] A common source of requirements gaps is non-functional requirements such as testability, scalability, maintainability, usability, performance, and security.

Software faults occur through the following processes. A programmer makes an error (mistake), which results in a defect (fault, bug) in the software source code. If this defect is executed, in certain situations the system will produce wrong results, causing a failure.^[16] Not all defects will necessarily result in failures. For example, defects in dead code will never result in failures. A defect can turn into a failure when the environment is changed. Examples of these changes in environment include the software being run on a new computer hardware platform, alterations in source data or interacting with different software.^[16] A single defect may result in a wide range of failure symptoms.

Finding faults early[link]

It is commonly believed that the earlier a defect is found the cheaper it is to fix it. The following table shows the cost of fixing the defect depending on the stage it was found.^[17] For example, if a problem in the requirements is found only post-release, then it would cost 10–100 times more to fix than if it had already been found by the requirements review. Modern continuous deployment practices, and cloud-based services may cost less for re-deployment and maintenance than in the past.

Compatibility testing[link]

A common cause of software failure (real or perceived) is a lack of its compatibility with other application software, operating systems (or operating system versions, old or new), or target environments that differ greatly from the original (such as a terminal or GUI application intended to be run on the desktop now being required to become a web application, which must render in a web browser). For example, in the case of a lack of backward compatibility, this can occur because the programmers develop and test software only on the latest version of the target environment, which not all users may be running. This results in the unintended consequence that the latest work may not function on earlier versions of the target environment, or on older hardware that earlier versions of the target environment was capable of using. Sometimes such issues can be fixed by proactively abstracting operating system functionality into a separate program module or library.

Input combinations and preconditions[link]

A very fundamental problem with software testing is that testing under all combinations of inputs and preconditions (initial state) is not feasible, even with a simple product.^[13][18] This means that the number of defects in a software product can be very large and defects that occur infrequently are difficult to find in testing. More significantly, non-functional dimensions of quality (how it is supposed to be versus what it is supposed to do)—usability, scalability, performance, compatibility, reliability—can be highly subjective; something that constitutes sufficient value to one person may be intolerable to another.

Static vs. dynamic testing[link]

There are many approaches to software testing. Reviews, walkthroughs, or inspections are considered as static testing, whereas actually executing programmed code with a given set of test cases is referred to as dynamic testing. Static testing can be (and unfortunately in practice often is) omitted. Dynamic testing takes place when the program itself is used for the first time (which is generally considered the beginning of the testing stage). Dynamic testing may begin before the program is 100% complete in order to test particular sections of code (modules or discrete functions). Typical techniques for this are either using stubs/drivers or execution from a debugger environment. For example, spreadsheet programs are, by their very nature, tested to a large extent interactively ("on the fly"), with results displayed immediately after each calculation or text manipulation.

Software verification and validation[link]

Software testing is used in association with verification and validation:^[19]

• Verification: Have we built the software right? (i.e., does it implement the requirements).
• Validation: Have we built the right software? (i.e., do the requirements satisfy the customer).

The terms verification and validation are commonly used interchangeably in the industry; it is also common to see these two terms incorrectly defined. According to the IEEE Standard Glossary of Software Engineering Terminology:

Verification is the process of evaluating a system or component to determine whether the products of a given development phase satisfy the conditions imposed at the start of that phase.

Validation is the process of evaluating a system or component during or at the end of the development process to determine whether it satisfies specified requirements.

According to the IS0 9000 standard:

Verification is confirmation by examination and through provision of objective evidence that specified requirements have been fulfilled.

Validation is confirmation by examination and through provision of objective evidence that the requirements for a specific intended use or application have been fulfilled.

The software testing team[link]

Software testing can be done by software testers. Until the 1980s the term "software tester" was used generally, but later it was also seen as a separate profession. Regarding the periods and the different goals in software testing,^[20] different roles have been established: manager, test lead, test designer, tester, automation developer, and test administrator.

Software quality assurance (SQA)[link]

Though controversial, software testing is a part of the software quality assurance (SQA) process.^[13] In SQA, software process specialists and auditors are concerned for the software development process rather than just the artifacts such as documentation, code and systems. They examine and change the software engineering process itself to reduce the number of faults that end up in the delivered software: the so-called defect rate. What constitutes an "acceptable defect rate" depends on the nature of the software; A flight simulator video game would have much higher defect tolerance than software for an actual airplane. Although there are close links with SQA, testing departments often exist independently, and there may be no SQA function in some companies. Software testing is a task intended to detect defects in software by contrasting a computer program's expected results with its actual results for a given set of inputs. By contrast, QA (quality assurance) is the implementation of policies and procedures intended to prevent defects from occurring in the first place.

Testing methods[link]

The box approach[link]

Software testing methods are traditionally divided into white- and black-box testing. These two approaches are used to describe the point of view that a test engineer takes when designing test cases.

White-Box testing[link]

White-box testing is when the tester has access to the internal data structures and algorithms including the code that implements these.

Types of white-box testing

The following types of white-box testing exist:

• API testing (application programming interface) - testing of the application using public and private APIs
• Code coverage - creating tests to satisfy some criteria of code coverage (e.g., the test designer can create tests to cause all statements in the program to be executed at least once)
• Fault injection methods - intentionally introducing faults to gauge the efficacy of testing strategies
• Mutation testing methods
• Static testing - All types

Test coverage

White-box testing methods can also be used to evaluate the completeness of a test suite that was created with black-box testing methods. This allows the software team to examine parts of a system that are rarely tested and ensures that the most important function points have been tested.^[21]

Two common forms of code coverage are:

• Function coverage, which reports on functions executed
• Statement coverage, which reports on the number of lines executed to complete the test

They both return a code coverage metric, measured as a percentage.

Black-box testing[link]

Black-box testing treats the software as a "black box"—without any knowledge of internal implementation. Black-box testing methods include: equivalence partitioning, boundary value analysis, all-pairs testing, fuzz testing, model-based testing, exploratory testing and specification-based testing.

Specification-based testing: Aims to test the functionality of software according to the applicable requirements.^[22] Thus, the tester inputs data into, and only sees the output from, the test object. This level of testing usually requires thorough test cases to be provided to the tester, who then can simply verify that for a given input, the output value (or behavior), either "is" or "is not" the same as the expected value specified in the test case.

Specification-based testing is necessary, but it is insufficient to guard against certain risks.^[23]

Advantages and disadvantages: The black-box tester has no "bonds" with the code, and a tester's perception is very simple: a code must have bugs. Using the principle, "Ask and you shall receive," black-box testers find bugs where programmers do not. On the other hand, black-box testing has been said to be "like a walk in a dark labyrinth without a flashlight," because the tester doesn't know how the software being tested was actually constructed. As a result, there are situations when (1) a tester writes many test cases to check something that could have been tested by only one test case, and/or (2) some parts of the back-end are not tested at all.

Therefore, black-box testing has the advantage of "an unaffiliated opinion", on the one hand, and the disadvantage of "blind exploring", on the other. ^[24]

Grey-box testing[link]

Grey-box testing (American spelling: gray-box testing) involves having knowledge of internal data structures and algorithms for purposes of designing tests, while executing those tests at the user, or black-box level. The tester is not required to have full access to the software's source code.^{[25][not in citation given]} Manipulating input data and formatting output do not qualify as grey-box, because the input and output are clearly outside of the "black box" that we are calling the system under test. This distinction is particularly important when conducting integration testing between two modules of code written by two different developers, where only the interfaces are exposed for test. However, modifying a data repository does qualify as grey-box, as the user would not normally be able to change the data outside of the system under test. Grey-box testing may also include reverse engineering to determine, for instance, boundary values or error messages.

By knowing the underlying concepts of how the software works, the tester makes better-informed testing choices while testing the software from outside. Typically, a grey-box tester will be permitted to set up his testing environment; for instance, seeding a database; and the tester can observe the state of the product being tested after performing certain actions. For instance, in testing a database product he/she may fire an SQL query on the database and then observe the database, to ensure that the expected changes have been reflected. Grey-box testing implements intelligent test scenarios, based on limited information. This will particularly apply to data type handling, exception handling, and so on.^[26]

Visual testing[link]

The aim of visual testing is to provide developers with the ability to examine what was happening at the point of software failure by presenting the data in such a way that the developer can easily find the information he requires, and the information is expressed clearly.^[27][28]

At the core of visual testing is the idea that showing someone a problem (or a test failure), rather than just describing it, greatly increases clarity and understanding. Visual testing therefore requires the recording of the entire test process – capturing everything that occurs on the test system in video format. Output videos are supplemented by real-time tester input via picture-in-a-picture webcam and audio commentary from microphones.

Visual testing provides a number of advantages. The quality of communication is increased dramatically because testers can show the problem (and the events leading up to it) to the developer as opposed to just describing it and the need to replicate test failures will cease to exist in many cases. The developer will have all the evidence he requires of a test failure and can instead focus on the cause of the fault and how it should be fixed.

Visual testing is particularly well-suited for environments that deploy agile methods in their development of software, since agile methods require greater communication between testers and developers and collaboration within small teams.^{[citation needed]}

Ad hoc testing and exploratory testing are important methodologies for checking software integrity, because they require less preparation time to implement, whilst important bugs can be found quickly. In ad hoc testing, where testing takes place in an improvised, impromptu way, the ability of a test tool to visually record everything that occurs on a system becomes very important.^{[clarification needed][citation needed]}

Visual testing is gathering recognition in customer acceptance and usability testing, because the test can be used by many individuals involved in the development process.^{[citation needed]} For the customer, it becomes easy to provide detailed bug reports and feedback, and for program users, visual testing can record user actions on screen, as well as their voice and image, to provide a complete picture at the time of software failure for the developer.

Testing levels[link]

Tests are frequently grouped by where they are added in the software development process, or by the level of specificity of the test. The main levels during the development process as defined by the SWEBOK guide are unit-, integration-, and system testing that are distinguished by the test target without implying a specific process model.^[29] Other test levels are classified by the testing objective.^[29]

Test target[link]

Unit testing[link]

Unit testing, also known as component testing, refers to tests that verify the functionality of a specific section of code, usually at the function level. In an object-oriented environment, this is usually at the class level, and the minimal unit tests include the constructors and destructors.^[30]

These types of tests are usually written by developers as they work on code (white-box style), to ensure that the specific function is working as expected. One function might have multiple tests, to catch corner cases or other branches in the code. Unit testing alone cannot verify the functionality of a piece of software, but rather is used to assure that the building blocks the software uses work independently of each other.

Integration testing[link]

Integration testing is any type of software testing that seeks to verify the interfaces between components against a software design. Software components may be integrated in an iterative way or all together ("big bang"). Normally the former is considered a better practice since it allows interface issues to be localised more quickly and fixed.

Integration testing works to expose defects in the interfaces and interaction between integrated components (modules). Progressively larger groups of tested software components corresponding to elements of the architectural design are integrated and tested until the software works as a system.^[31]

System testing[link]

System testing tests a completely integrated system to verify that it meets its requirements.^[32]

System integration testing[link]

System integration testing verifies that a system is integrated to any external or third-party systems defined in the system requirements.^{[citation needed]}

Objectives of testing[link]

Installation testing[link]

An Installation test assures that the system is installed correctly and working at actual customer's hardware.

Sanity testing[link]

A Sanity test determines whether it is reasonable to proceed with further testing.

Regression testing[link]

Regression testing focuses on finding defects after a major code change has occurred. Specifically, it seeks to uncover software regressions, or old bugs that have come back. Such regressions occur whenever software functionality that was previously working correctly stops working as intended. Typically, regressions occur as an unintended consequence of program changes, when the newly developed part of the software collides with the previously existing code. Common methods of regression testing include re-running previously run tests and checking whether previously fixed faults have re-emerged. The depth of testing depends on the phase in the release process and the risk of the added features. They can either be complete, for changes added late in the release or deemed to be risky, to very shallow, consisting of positive tests on each feature, if the changes are early in the release or deemed to be of low risk.

Acceptance testing[link]

Acceptance testing can mean one of two things:

1. A smoke test is used as an acceptance test prior to introducing a new build to the main testing process, i.e. before integration or regression.
2. Acceptance testing performed by the customer, often in their lab environment on their own hardware, is known as user acceptance testing (UAT). Acceptance testing may be performed as part of the hand-off process between any two phases of development.^{[citation needed]}

Alpha testing[link]

Alpha testing is simulated or actual operational testing by potential users/customers or an independent test team at the developers' site. Alpha testing is often employed for off-the-shelf software as a form of internal acceptance testing, before the software goes to beta testing.^[33]

Beta testing[link]

Beta testing comes after alpha testing and can be considered a form of external user acceptance testing. Versions of the software, known as beta versions, are released to a limited audience outside of the programming team. The software is released to groups of people so that further testing can ensure the product has few faults or bugs. Sometimes, beta versions are made available to the open public to increase the feedback field to a maximal number of future users.^{[citation needed]}

Non-functional testing[link]

Special methods exist to test non-functional aspects of software. In contrast to functional testing, which establishes the correct operation of the software (for example that it matches the expected behavior defined in the design requirements), non-functional testing verifies that the software functions properly even when it receives invalid or unexpected inputs. Software fault injection, in the form of fuzzing, is an example of non-functional testing. Non-functional testing, especially for software, is designed to establish whether the device under test can tolerate invalid or unexpected inputs, thereby establishing the robustness of input validation routines as well as error-management routines. Various commercial non-functional testing tools are linked from the software fault injection page; there are also numerous open-source and free software tools available that perform non-functional testing.

Software performance testing[link]

Performance testing is in general executed to determine how a system or sub-system performs in terms of responsiveness and stability under a particular workload. It can also serve to investigate, measure, validate or verify other quality attributes of the system, such as scalability, reliability and resource usage.

Load testing is primarily concerned with testing that the system can continue to operate under a specific load, whether that be large quantities of data or a large number of users. This is generally referred to as software scalability. The related load testing activity of when performed as a non-functional activity is often referred to as endurance testing. Volume testing is a way to test functionality. Stress testing is a way to test reliability under unexpected or rare workloads. Stability testing (often referred to as load or endurance testing) checks to see if the software can continuously function well in or above an acceptable period.

There is little agreement on what the specific goals of performance testing are. The terms load testing, performance testing, reliability testing, and volume testing, are often used interchangeably.

Usability testing[link]

Usability testing is needed to check if the user interface is easy to use and understand. It is concerned mainly with the use of the application.

Security testing[link]

Security testing is essential for software that processes confidential data to prevent system intrusion by hackers.

Internationalization and localization[link]

The general ability of software to be internationalized and localized can be automatically tested without actual translation, by using pseudolocalization. It will verify that the application still works, even after it has been translated into a new language or adapted for a new culture (such as different currencies or time zones).^[34]

Actual translation to human languages must be tested, too. Possible localization failures include:

• Software is often localized by translating a list of strings out of context, and the translator may choose the wrong translation for an ambiguous source string.
• Technical terminology may become inconsistent if the project is translated by several people without proper coordination or if the translator is imprudent.
• Literal word-for-word translations may sound inappropriate, artificial or too technical in the target language.
• Untranslated messages in the original language may be left hard coded in the source code.
• Some messages may be created automatically at run time and the resulting string may be ungrammatical, functionally incorrect, misleading or confusing.
• Software may use a keyboard shortcut which has no function on the source language's keyboard layout, but is used for typing characters in the layout of the target language.
• Software may lack support for the character encoding of the target language.
• Fonts and font sizes which are appropriate in the source language may be inappropriate in the target language; for example, CJK characters may become unreadable if the font is too small.
• A string in the target language may be longer than the software can handle. This may make the string partly invisible to the user or cause the software to crash or malfunction.
• Software may lack proper support for reading or writing bi-directional text.
• Software may display images with text that was not localized.
• Localized operating systems may have differently-named system configuration files and environment variables and different formats for date and currency.

To avoid these and other localization problems, a tester who knows the target language must run the program with all the possible use cases for translation to see if the messages are readable, translated correctly in context and do not cause failures.

Destructive testing[link]

Destructive testing attempts to cause the software or a sub-system to fail, in order to test its robustness.

The testing process[link]

Traditional CMMI or waterfall development model[link]

A common practice of software testing is that testing is performed by an independent group of testers after the functionality is developed, before it is shipped to the customer.^[35] This practice often results in the testing phase being used as a project buffer to compensate for project delays, thereby compromising the time devoted to testing.^[36]

Another practice is to start software testing at the same moment the project starts and it is a continuous process until the project finishes.^[37]

Agile or Extreme development model[link]

In contrast, some emerging software disciplines such as extreme programming and the agile software development movement, adhere to a "test-driven software development" model. In this process, unit tests are written first, by the software engineers (often with pair programming in the extreme programming methodology). Of course these tests fail initially; as they are expected to. Then as code is written it passes incrementally larger portions of the test suites. The test suites are continuously updated as new failure conditions and corner cases are discovered, and they are integrated with any regression tests that are developed. Unit tests are maintained along with the rest of the software source code and generally integrated into the build process (with inherently interactive tests being relegated to a partially manual build acceptance process). The ultimate goal of this test process is to achieve continuous integration where software updates can be published to the public frequently. ^{[38] [39]}

A sample testing cycle[link]

Although variations exist between organizations, there is a typical cycle for testing.^[40] The sample below is common among organizations employing the Waterfall development model.

• Requirements analysis: Testing should begin in the requirements phase of the software development life cycle. During the design phase, testers work with developers in determining what aspects of a design are testable and with what parameters those tests work.
• Test planning: Test strategy, test plan, testbed creation. Since many activities will be carried out during testing, a plan is needed.
• Test development: Test procedures, test scenarios, test cases, test datasets, test scripts to use in testing software.
• Test execution: Testers execute the software based on the plans and test documents then report any errors found to the development team.
• Test reporting: Once testing is completed, testers generate metrics and make final reports on their test effort and whether or not the software tested is ready for release.
• Test result analysis: Or Defect Analysis, is done by the development team usually along with the client, in order to decide what defects should be assigned, fixed, rejected (i.e. found software working properly) or deferred to be dealt with later.
• Defect Retesting: Once a defect has been dealt with by the development team, it is retested by the testing team. AKA Resolution testing.
• Regression testing: It is common to have a small test program built of a subset of tests, for each integration of new, modified, or fixed software, in order to ensure that the latest delivery has not ruined anything, and that the software product as a whole is still working correctly.
• Test Closure: Once the test meets the exit criteria, the activities such as capturing the key outputs, lessons learned, results, logs, documents related to the project are archived and used as a reference for future projects.

Automated testing[link]

Many programming groups are relying more and more on automated testing, especially groups that use test-driven development. There are many frameworks to write tests in, and continuous integration software will run tests automatically every time code is checked into a version control system.

While automation cannot reproduce everything that a human can do (and all the ways they think of doing it), it can be very useful for regression testing. However, it does require a well-developed test suite of testing scripts in order to be truly useful.

Testing tools[link]

Program testing and fault detection can be aided significantly by testing tools and debuggers. Testing/debug tools include features such as:

• Program monitors, permitting full or partial monitoring of program code including:
  • Instruction set simulator, permitting complete instruction level monitoring and trace facilities
  • Program animation, permitting step-by-step execution and conditional breakpoint at source level or in machine code
  • Code coverage reports
• Formatted dump or symbolic debugging, tools allowing inspection of program variables on error or at chosen points
• Automated functional GUI testing tools are used to repeat system-level tests through the GUI
• Benchmarks, allowing run-time performance comparisons to be made
• Performance analysis (or profiling tools) that can help to highlight hot spots and resource usage

Some of these features may be incorporated into an Integrated Development Environment (IDE).

• A regression testing technique is to have a standard set of tests, which cover existing functionality that result in persistent tabular data, and to compare pre-change data to post-change data, where there should not be differences, using a tool like diffkit. Differences detected indicate unexpected functionality changes or "regression".

Measurement in software testing[link]

Usually, quality is constrained to such topics as correctness, completeness, security,^{[citation needed]} but can also include more technical requirements as described under the ISO standard ISO/IEC 9126, such as capability, reliability, efficiency, portability, maintainability, compatibility, and usability.

There are a number of frequently-used software measures, often called metrics, which are used to assist in determining the state of the software or the adequacy of the testing.

Testing artifacts[link]

The software testing process can produce several artifacts.

Test plan

A test specification is called a test plan. The developers are well aware what test plans will be executed and this information is made available to management and the developers. The idea is to make them more cautious when developing their code or making additional changes. Some companies have a higher-level document called a test strategy.

Traceability matrix

A traceability matrix is a table that correlates requirements or design documents to test documents. It is used to change tests when related source documents are changed, to select test cases for execution when planning for regression tests by considering requirement coverage.

Test case

A test case normally consists of a unique identifier, requirement references from a design specification, preconditions, events, a series of steps (also known as actions) to follow, input, output, expected result, and actual result. Clinically defined a test case is an input and an expected result.^[41] This can be as pragmatic as 'for condition x your derived result is y', whereas other test cases described in more detail the input scenario and what results might be expected. It can occasionally be a series of steps (but often steps are contained in a separate test procedure that can be exercised against multiple test cases, as a matter of economy) but with one expected result or expected outcome. The optional fields are a test case ID, test step, or order of execution number, related requirement(s), depth, test category, author, and check boxes for whether the test is automatable and has been automated. Larger test cases may also contain prerequisite states or steps, and descriptions. A test case should also contain a place for the actual result. These steps can be stored in a word processor document, spreadsheet, database, or other common repository. In a database system, you may also be able to see past test results, who generated the results, and what system configuration was used to generate those results. These past results would usually be stored in a separate table.

Test script

A test script is a procedure, or programing code that replicates user actions. Initially the term was derived from the product of work created by automated regression test tools. Test Case will be a baseline to create test scripts using a tool or a program.

Test suite

The most common term for a collection of test cases is a test suite. The test suite often also contains more detailed instructions or goals for each collection of test cases. It definitely contains a section where the tester identifies the system configuration used during testing. A group of test cases may also contain prerequisite states or steps, and descriptions of the following tests.

Test data

In most cases, multiple sets of values or data are used to test the same functionality of a particular feature. All the test values and changeable environmental components are collected in separate files and stored as test data. It is also useful to provide this data to the client and with the product or a project.

Test harness

The software, tools, samples of data input and output, and configurations are all referred to collectively as a test harness.

Certifications[link]

Several certification programs exist to support the professional aspirations of software testers and quality assurance specialists. No certification currently offered actually requires the applicant to demonstrate the ability to test software. No certification is based on a widely accepted body of knowledge. This has led some to declare that the testing field is not ready for certification.^[42] Certification itself cannot measure an individual's productivity, their skill, or practical knowledge, and cannot guarantee their competence, or professionalism as a tester.^[43]

Software testing certification types

• Exam-based: Formalized exams, which need to be passed; can also be learned by self-study [e.g., for ISTQB or QAI]^[44]
• Education-based: Instructor-led sessions, where each course has to be passed [e.g., International Institute for Software Testing (IIST)].

Testing certifications

• Certified Associate in Software Testing (CAST) offered by the QAI ^[45]
• CATe offered by the International Institute for Software Testing^[46]
• Certified Manager in Software Testing (CMST) offered by the QAI ^[45]
• Certified Software Tester (CSTE) offered by the Quality Assurance Institute (QAI)^[45]
• Certified Software Test Professional (CSTP) offered by the International Institute for Software Testing^[46]
• CSTP (TM) (Australian Version) offered by K. J. Ross & Associates^[47]
• ISEB offered by the Information Systems Examinations Board
• ISTQB Certified Tester, Foundation Level (CTFL) offered by the International Software Testing Qualification Board ^[48][49]
• ISTQB Certified Tester, Advanced Level (CTAL) offered by the International Software Testing Qualification Board ^[48][49]
• TMPF TMap Next Foundation offered by the Examination Institute for Information Science^[50]
• TMPA TMap Next Advanced offered by the Examination Institute for Information Science^[50]

Quality assurance certifications

• CMSQ offered by the Quality Assurance Institute (QAI).^[45]
• CSQA offered by the Quality Assurance Institute (QAI)^[45]
• CSQE offered by the American Society for Quality (ASQ)^[51]
• CQIA offered by the American Society for Quality (ASQ)^[51]

Controversy[link]

Some of the major software testing controversies include:

What constitutes responsible software testing? 

Members of the "context-driven" school of testing^[52] believe that there are no "best practices" of testing, but rather that testing is a set of skills that allow the tester to select or invent testing practices to suit each unique situation.^[53]

Agile vs. traditional 

Should testers learn to work under conditions of uncertainty and constant change or should they aim at process "maturity"? The agile testing movement has received growing popularity since 2006 mainly in commercial circles,^[54][55] whereas government and military^[56] software providers use this methodology but also the traditional test-last models (e.g. in the Waterfall model).^{[citation needed]}

Exploratory test vs. scripted

^[57] Should tests be designed at the same time as they are executed or should they be designed beforehand?

Manual testing vs. automated 

Some writers believe that test automation is so expensive relative to its value that it should be used sparingly.^[58] More in particular, test-driven development states that developers should write unit-tests of the XUnit type before coding the functionality. The tests then can be considered as a way to capture and implement the requirements.

Software design vs. software implementation

^[59] Should testing be carried out only at the end or throughout the whole process?

Who watches the watchmen? 

The idea is that any form of observation is also an interaction—the act of testing can also affect that which is being tested.^[60]

See also[link]

Software Testing portal

	Book: Software testing
Wikipedia books are collections of articles that can be downloaded or ordered in print.

• Acceptance testing
• All-pairs testing
• Automated testing
• Dynamic program analysis
• Formal verification
• GUI software testing
• Independent test organization
• Manual testing
• Orthogonal array testing
• Pair Testing
• Reverse semantic traceability
• Software testability
• Static code analysis
• Orthogonal Defect Classification
• Test management tools
• Web testing

Further reading[link]

• Bertrand Meyer, "Seven Principles of Software Testing," Computer, vol. 41, no. 8, pp. 99-101, Aug. 2008, doi:10.1109/MC.2008.306; available online.

References[link]

External links[link]

At Wikiversity you can learn more and teach others about Software testing at: The Department of Software testing

• Software testing tools and products at the Open Directory Project
• "Software that makes Software better" Economist.com
• Automated software testing metrics including manual testing metrics