Unit
Testing a small part of code , instead of the finished product.
- Write code easier to test
- In depth tests.
Integration
Individual code components are merged together or with preexisting software project. The overall idea is a "building block" approach, in which verified assemblages are added to a verified base which is then used to support the integration testing of further assemblages.
System
System testing is the prime objective of any software product.It conducts testing of whole software product to identify the errors in software.
Regression
Regression testing is where testing seeks to uncover new software bugs or 'regression' in existing function and non functional areas of a system after changes such as enhancements patches or configuration changes have been made to them.
System test > Bug fixes > Regression test after fixes implemented
Acceptance
Acceptance testing should be completed at most stages of the development life cycle. It ensures the product matches the requirement from the customer, one of the most important test phases.
Alpha
In house testing, this phase is where you would expect to find the most bugs.After alpha testing is complete, software is then Beta tested.
Beta
Improve the quality of the product, integrate customer input on the complete product and ensure release readiness.Usually completed just prior to software launch.Tested in the "real world" with "real customer" and the feedback can cover every element of the product.
V model
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Agile
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