Black box testing – This kind of Testing is not based on any knowledge of internal design or coding. These Tests are based on requirements and functionality.
White box testing – This is based on knowledge of the internal logic of an application’s code. Tests are based on coverage of code statements, branches, paths, conditions.
Unit testing – the most ‘micro’ scale of testing; to test particular functions or code modules. This is typically done by the programmer and not by testers, as it requires detailed knowledge of the internal program, design and code. Not always easily done unless the application has a well-designed architecture with tight code; may require developing test driver modules or test harnesses.
Incremental integration testing – continuous testing of an application when new functionality is added; requires that various aspects of an application’s functionality be independent enough to work separately before all parts of the program are completed, or that test drivers be developed as needed; done by programmers or by testers.
Integration testing – testing of combined parts of an application to determine if they functioning together correctly. The ‘parts’ can be code modules, individual applications, client and server applications on a network, etc. This type of testing is especially relevant to client/server and distributed systems.
Functional testing – this testing is geared to functional requirements of an application; this type of testing should be done by testers. This doesn’t mean that the programmers shouldn’t check that their code works before releasing it (which of course applies to any stage of testing.)
System testing – this is based on the overall requirements specifications; covers all the combined parts of a system.
End-to-end testing – this is similar to system testing; involves testing of a complete application environment in a situation that imitate real-world use, such as interacting with a database, using network communications, or interacting with other hardware, applications, or systems.
Sanity testing or smoke testing – typically this is an initial testing to determine whether a new software version is performing well enough to accept it for a major testing effort. For example, if the new software is crashing systems in every 5 minutes, making down the systems to crawl or corrupting databases, the software may not be in a normal condition to warrant further testing in its current state.
Regression testing – this is re-testing after bug fixes or modifications of the software. It is difficult to determine how much re-testing is needed, especially at the end of the development cycle. Automated testing tools are very useful for this type of testing.
Acceptance testing – this can be said as a final testing and this was done based on specifications of the end-user or customer, or based on use by end-users/customers over some limited period of time.
Load testing – this is nothing but testing an application under heavy loads, such as testing a web site under a range of loads to determine at what point the system’s response time degrades or fails.
Stress testing – the term often used interchangeably with ‘load’ and ‘performance’ testing. Also used to describe such tests as system functional testing while under unusually heavy loads, heavy repetition of certain actions or inputs, input of large numerical values, large complex queries to a database system, etc.
Performance testing – the term often used interchangeably with ‘stress’ and ‘load’ testing. Ideally ‘performance’ testing is defined in requirements documentation or QA or Test Plans.
Usability testing – this testing is done for ‘user-friendliness’. Clearly this is subjective, and will depend on the targeted end-user or customer. User interviews, surveys, video recording of user sessions, and other techniques can be used. Programmers and testers are usually not suited as usability testers.
Compatibility testing – testing how well the software performs in a particular hardware/software/operating system/network/etc. environment.
User acceptance testing – determining if software is satisfactory to a end-user or a customer.
Comparison testing – comparing software weaknesses and strengths to other competing products.
Alpha testing – testing an application when development is nearing completion; minor design changes may still be made as a result of such testing. This is typically done by end-users or others, but not by the programmers or testers.
Beta testing – testing when development and testing are essentially completed and final bugs and problems need to be found before final release. This is typically done by end-users or others, not by programmers or testers.
Mutation testing – a method for determining a set of test data or test cases is useful or not, by intentionally introducing various code changes (‘bugs’) and retesting with the original test data/cases to determine if the ‘bugs’ are detected.