Software Testing

Software Testing is a method to assess the functionality of the software program.

The process checks whether the actual software matches the expected requirements and ensures the software is bug-free.

The purpose of software testing is to identify the errors, faults, or missing requirements in contrast to actual requirements.

It mainly aims at measuring the specification, functionality, and performance of a software program or application.

Software testing can be divided into two steps:

1. Verification: It refers to the set of tasks that ensure that the software correctly implements a specific function. It means “Are we building the product right?”.

2. Validation: It refers to a different set of tasks that ensure that the software that has been built is traceable to customer requirements. It means “Are we building the right product?”.

Software Testing can be broadly classified into 3 types:

1. Functional Testing:

   Functional testing is a type of software testing that validates the software systems against the functional requirements. It is performed to check whether the application is working as per the software’s functional requirements or not. Various types of functional testing are Unit testing, Integration testing, System testing, Smoke testing, and so on.

2. Non-functional Testing:

   Non-functional testing is a type of software testing that checks the application for non-functional requirements like performance, scalability, portability, stress, etc. Various types of non-functional testing are Performance testing, Stress testing, Usability Testing, and so on.

3. Maintenance Testing:

   Maintenance testing is the process of changing, modifying, and updating the software to keep up with the customer’s needs. It involves regression testing that verifies that recent changes to the code have not adversely affected other previously working parts of the software.

Apart from the above classification software testing can be further divided into 2 more ways of testing:

1. Manual Testing: Manual testing includes testing software manually, i.e., without using any automation tool or script. In this type, the tester takes over the role of an end-user and tests the software to identify any unexpected behavior or bug. There are different stages for manual testing such as unit testing, integration testing, system testing, and user acceptance testing. Testers use test plans, test cases, or test scenarios to test software to ensure the completeness of testing. Manual testing also includes exploratory testing, as testers explore the software to identify errors in it.

2. Automation Testing: Automation testing, which is also known as Test Automation, is when the tester writes scripts and uses another software to test the product. This process involves the automation of a manual process. Automation Testing is used to re-run the test scenarios quickly and repeatedly, that were performed manually in manual testing. Apart from regression testing, automation testing is also used to test the application from a load, performance, and stress point of view. It increases the test coverage, improves accuracy, and saves time and money when compared to manual testing.

Different Types of Software Testing Techniques

Software testing techniques can be majorly classified into two categories:

1. Black Box Testing: Black box technique of testing in which the tester doesn’t have access to the source code of the software and is conducted at the software interface without any concern with the internal logical structure of the software known as black-box testing.

2. White-Box Testing: White box technique of testing in which the tester is aware of the internal workings of the product, has access to its source code, and is conducted by making sure that all internal operations are performed according to the specifications is known as white box testing.

3. Grey Box Testing: Grey Box technique is testing in which the testers should have knowledge of implementation, however, they need not be experts.

Black Box Testing	White Box Testing
Internal workings of an application are not required.	Knowledge of the internal workings is a must.
Also known as closed box/data-driven testing.	Also known as clear box/structural testing.
End users, testers, and developers.	Normally done by testers and developers.
This can only be done by a trial and error method.	Data domains and internal boundaries can be better tested.

Different Levels of Software Testing

Software level testing can be majorly classified into 4 levels:

1. Unit Testing: Unit testing is a level of the software testing process where individual units/components of a software/system are tested. The purpose is to validate that each unit of the software performs as designed.

2. Integration Testing: Integration testing is a level of the software testing process where individual units are combined and tested as a group. The purpose of this level of testing is to expose faults in the interaction between integrated units.

3. System Testing: System testing is a level of the software testing process where a complete, integrated system/software is tested. The purpose of this test is to evaluate the system’s compliance with the specified requirements.

4. Acceptance Testing: Acceptance testing is a level of the software testing process where a system is tested for acceptability. The purpose of this test is to evaluate the system’s compliance with the business requirements and assess whether it is acceptable for delivery.