Levels of Testing | Levels of Software Testing | Software Testing Levels

Testing is used to detect faults introduced during specification and design stages as well as coding stages. Due to this, different levels of testing are used in the testing process. Each level of testing aims to test different aspects of the system. 

The basic levels of testing are:

• Unit testing
• Integration testing
• System testing

 

Unit Testing:

Unit testing is the process of checking small pieces of code to ensure that the individual parts of a program work properly on their own. This involves the tests carried out on modules, which make up a system. During unit testing, the individual components or units of a program are tested. Unit testing focuses first on the modules, independently of one another, to locate errors.

Unit testing is the process of taking a module and running it in isolation from the rest of the software product by using prepared test cases and comparing the actual results with the results predicted by the specifications and design of the module.

In this level, different modules are tested against the specification produced during design for the modules. Unit testing is essentially for verification of the code produced during the code phase. That is, the goal of this testing is to test the internal logic of the modules. Due to its close association with coding, the coding phase is frequently called “coding and unit testing”.

The primary objective of executing the unit testing is to confirm the unit components with their performance.

 

Integration Testing:

Once we are successfully implementing the unit testing, we will go integration testing. In this level, many unit-tested modules are combined into subsystems, which are then tested. The goal of this testing level is to see if the modules can be integrated properly.

Integration testing ensures that an entire, integrated system meets a set of requirements. The purpose of executing the integration testing is to test the statement's accuracy between each module.

System Testing:

Whenever we are done with the unit and integration testing, we can proceed with the system testing. Here the entire software is tested. The reference document for this process is the requirements document. The goal is to see if the software meets its requirements.

The purpose of system testing is to validate an application’s accuracy and completeness in performing the functions as designed.

FAQ:

1. What are the levels of testing?

2. What are the three levels of testing in software engineering?

3. What are different types of testing?

4. What are the different levels of testing?