Testing types

Below are the different Testing types and or Levels

Unit testing refers to tests to verify the functionality of a particular section of code, usually the function. In an object-oriented, it is usually at the classroom level and minimal unit tests include constructors and destructions.
These types of tests are usually by the developers in their work on the code (white box-style writing), to ensure that the specific function works as expected. A function can take several tests to take account of cases of angle or other areas in the code. Unit testing is not the functionality of the software, but is used to ensure that software components to work independently of one another using.
Unit testing is also called the test components.

What is The Integration Test

Integration tests for all types of software testing, test to verify the interfaces between the components in a software project. The software components can be integrated through an iterative process, or all together (Big Bang). Usually the first is a best-practice interface allows, because more problems to be quickly and correctly.
Integration testing work to the defects in the interfaces and interactions between integrated components (modules) suspend. Increasingly larger groups of tested software components corresponding to elements of architectural design are integrated and until the software works as a system tested [26].
What is Test System:
to evaluate test system software or hardware testing on a comprehensive and integrated system to meet its requirements implemented. System test is under the Black-box testing, and as such should not require any knowledge of the interior of code or logic.
Typically, system testing takes, passed as input, all the "integrated software components," the successful integration testing and system software are integrated with the existing hardware system (s). The purpose of the examination is to recognize the integration, inconsistencies between the software units that are integrated together (called assemblages) or between one of the modules and devices. Test system is a more restrictive type of tests, but attempts to identify deficiencies in both the inter-assemblages "and also within the entire system.

What is Regression testing
was committed regression testing focused on the search for defects after a significant change in the code. More specifically, regression software to detect errors or old, are returned. This software features regressions occur properly works as intended, if the work was previously shut down. In general, regressions occur as a result of unforeseen changes in the program when the top part of the new software conflicts with existing code. Common methods of regression tests are run again already run tests and check whether errors have been corrected, had reappeared. The depth of analysis depends on the stage of the process of liberation and the risk of new features. You can be completely made up for the changes included in the statement of purpose or considered vulnerable, very flat, of positive tests for each function, when the changes first seen in the press or low risk.

What is Acceptance testing Acceptance testing can mean two things:

   1st A smoke test is used as an acceptance test prior to any new construction for the main study, ie before the integration or regression.
   2nd Acceptance testing performed by the client, often in their own test environment HW, we know that the user acceptance testing (UAT). Acceptance tests can be in the process of hand-offs conducted between the two phases of development.

What is Alpha testing Alpha testing is simulated or actual operational testing by customers or potential users of a test team of independent developers. alpha is often used for off-the-shelf software used as a form of internal acceptance testing before the software goes into beta testing. [Edit]
What is Beta Testing Beta testing comes after alpha. Versions of the software are known as beta versions released for a limited time outside the programming team. The software is available for groups of people, so that further tests to ensure that the product has few faults or bugs. Sometimes, beta versions are made available to the public to the information field to enhance a maximum number of future users.