What really constitutes of are the levels of testing in software? There are different levels of testing in software. It is important for a testing team to have a well-defined testing process structure that includes the different levels of testing. The levels of software testing help provide a basic framework or structure where software quality can be improved, maintained and enhanced over time.

Some of the most common levels of software testing are.
· Unit Testing
· Integration Testing
· System Testing
· User Acceptance Testing (UAT)
· Beta Testing

Every level in these levels of testing in software has a specific goal and purpose. Your testing team should always have a solid, well-defined goal when it comes to carrying out any type of testing activity. Specialized goals and objectives must be in place for all types of testing so that you can track your software quality over time.

Defining the Levels of Testing in Software

1. Unit testing

The first level is unit testing. Unit testing is performed on the smallest units of source code. Unit testing isolates units of source code from one another to test for functional errors. Unit tests are usually written by the programmer that developed the unit, because that software tester understands the specifics of the code that he or she wrote. The primary purpose of unit testing is to ensure that each unit of source code works as it should and there are no bugs introducing into these smaller components. When working with source code the unit test is the best way to assure that the source code is in a state ready for integration.

2. Integration testing

Integration testing is performed on all the components of a program or system to make sure that they work together in combination. Integration testing is performed when all the pieces of software work in unison. “Integration in software development means making two or more software modules work together.

Integration testing is different from unit testing because it attempts to determine the effectiveness of the software as a whole. Unit tests will show that each unit is functioning correctly and that all units can function together. Integration testing will show if two units do not work together and must be modified to meet the goal and expectations of the overall program.

3. System testing

System testing is a group of tests that a tester will perform on a complete system to ensure that it functions as intended. In addition, the term beta test is sometimes applied to other types of software applications or components as well as hardware and non-software systems.

System testing is the last step of software development before software or hardware is released to the customers or customers’ customers for use. It is also known as Beta testing. If the program is not working as intended, it will be returned for revision before releasing it to the public. This allows the tester to work with users and give feedback on their experience with the program before it goes live.

4. User Acceptance Testing

In this case, though the customer plays an important role in the testing, they are not actually performing the testing themselves. Instead they play a more advisory role in helping to create a test plan and providing important information on how they expect the product to function.

5. Beta Testing

Beta testing is the term used when the product is officially released to the public.
The beta tester will be using the program as any other user of the program would, but is providing feedback on their experience with it to help improve it before it is officially available.

Conclusion

Each of these levels forms a spectrum in which different types of software testing can occur. For example, unit testing can be seen as a subset of functional testing. It also possible that integration testing could be seen as a subset of system testing.

Read more about alpha and beta testing here.