What are different types of white box testing? Part 1

White-box testing or clear box testing, transparent box testing, glass box testing, structural testing as it is also known can be defined as a method for testing software applications or programs. White box testing includes techniques that are used to test the program or algorithmic structures and working of that particular software application in opposition to its functionalities or the results of its black box tests.

White-box testing can be defined as a methodology to verify the source code of the software system if it works as expected or not. White box testing is a synonym for structural testing.

There are certain levels only at which white box testing can be applied. The levels have been given below in the list:
- Unit level
- Integration level and
- System level
- Acceptance level
- Regression level
- Beta level

Unit level testing:

This type of white box testing is used for testing the individual units or modules of the software system. Sometimes it also tests a group of modules. A unit is the smallest part of a program and cannot be divided further into smaller parts. Units form the basic structure of a software system. Unit level white box testing is performed to check whether or not the unit is working as expected. White box testing is done to ensure whether the unit is working properly or not so that later it can be integrated with the other units of the system. It is important to test units at this level because later after integration it becomes difficult to find errors. The software engineer who has written the code only knows where the potential bugs can be found. Others cannot track them. Therefore, such kinds of flaws are completely in the privacy of the writer. Unit level white box testing can find up to 65 percent of the total flaws.

- Integration level testing:
In this type of white box testing the software components and the hardware components are integrated and the program is executed. This is done mainly to determine whether both of the software units and hardware units are working together in harmony. It includes designing of test cases which check the user interfaces of the two components.