Basics of Software testing- 1

Basics of Software testing –

What is “Software Testing” - There are many definitions available on the internet given by various scholars in this field and everybody’s definition is different. Ask this question to a 1 year experienced person he will give you a bookish answer and If you ask this question to a person having 4 OR more years of experience in this field he might not able to give you a perfect answer . I would like to define it in my terms which may be similar with any scholars definition. As per my experience Software testing is an activity/phase/process in SDLC where in we test whether the software is working as per the its requirement specification and in turn we measure the quality of the software developed. It is a process of executing a program or system with the intent of finding errors and evaluating it for conformance with the requirements specification.

Now on the basis of approach followed testing can be divided into –
- White Box
- Black Box

When we say that we are following/doing “White Box testing”, we mean that a testing activity in which we have access to the code of the system/module/ function we are testing and we are aware of the logic implemented in it. This knowledge may help us finding out the right place where the bug/defect has occurred and wrongly implemented logic.

Coming on to “Black Box testing”, In this type of testing we do not have access to the actual code of the system neither we have knowledge of the logic implemented. In this type of testing , tester is more concerned about the output which he/she gets from the system on the basis of the input given.

On the basis of types, there are four types of testing –
- Unit testing
- Functional testing
- Integration testing
- System testing

Unit testing is the primary testing activity carried out at the code level. It intend to find out the fault/bug in smallest unit of a project – A Program / Function. It follows “WHITE BOX” approach and is different from debugging in the sense that debugging is executing the program step by step to diagnose a problem where as Unit testing is broader activity which covers not only executing a program but also checking the placement of elements on the screen, performing nominal operations with them and related activities. For eg. If my program accepts input in a text field ‘T’ and it is not accepting that then debugging comes into picture. By executing the program step by step we will find out where the problem is. While in the same example Unit testing refers to testing whether the user is able to input the characters, fields are getting displayed at proper place and so on. Developers are responsible for UNIT TESTING.

Functional Testing is a step further to unit testing. This refers to testing functionality of the application/modules of the application as per the requirement specification. Test Engineers are responsible for it and they write test cases / scripts for performing functional testing.

Integration Testing is another steps further in testing of an application and it refers to testing the combined parts of the application , interaction of different parts of applications with each other. Under this different application parts (modules) are combined together and the application behavior, data flow between these parts, interaction between them is tested .

Systems Testing is the last testing activity conducted on any software system / application. It refers to testing the system as whole and confirm that whether it meets the requirements OR not. Apart from functional requirements systems testing also covers non functional requirements like performance, usability, security, reliability maintainability and other related factors.


As always, suggestions / comments welcome. Also I would like to have inputs on what more topics can be written


-Amit