Every developed software including windows applications, web applications, mobile applications, etc... will definitely contain some bugs. It needs to be tested and rectified before the finalization stage. Experts will work on developed software and figure out the bugs and also they will suggest updations that will improve user experience. We call those experts as Software testers. They interrogate every possibility of error occurrences from the development stage onwards and outputs an error-free software product to the customer or end-user.
The software tester plays a key role in software quality control and quality assurance. An error-free and user-friendly software make your product genuine and widely acceptable. So, software testing is one of the focussed areas of the software development industry.
Software testing can be done either as manual or automated. Manual testing is carried out by software testers by analysing different test cases. But, automated testing uses different tools and algorithms for bug identification. There are different stages of manual testing like unit testing, integration testing, system testing, acceptance testing and performance testing.
More than one developers will work on any complicated software development by dividing the entire software into modules. The unit testing is done by software tester on each module individually after the developer completes its coding. Any issues at this level are solved and merge all modules together. After integrating these modules together, software tester will perform integration testing to check whether these combined modules communicate with each other effectively. The next level is system testing, that test the website/software from the beginning to the end after fixing all software integration errors. The beta version of the software is tested by real users and this testing is called acceptance testing. Performance testing evaluates how the website or software works. That includes the speed, scalability, stability of the website/application.
7 Principles Of Software Testing
Testing Shows Presence of Defects: No software can be developed 100% error-free. With software testing, it is possible to identify 75% of the major errors. Remaining 25% will present in the software undetected. But in some cases, the existing errors can make your application/website worst. So, it is necessary to execute maximum test cases for successful software output.
Early Testing: Testing will improve the quality of any software. Earlier the testing start, greater the software will perform. The software testing needs to be done from the initial stage of software development. That means, each and every module of the software needs to be tested properly and error resolved. Testing and error fixing on every stage of the software development life cycle will reduce the errors while deployment.
Exhaustive testing is impossible: One can test software with so many valid and invalid combinations of input strings. This will be time-consuming and requires unlimited effort. Still, the final result will be a delay and most of the bugs will remain undetected. This is why it is said that exhaustive testing is impossible. A software/website only needs to be tested with a few test cases that are selected based on the priority of error chances.
Defect clustering: In software development, any simple mistake on coding or designing can create a lot of errors in the software. If that root cause is identified, all those errors can be cleared immediately. Defect clustering means that most of the errors in the software will be present on a small number of modules. According to the ‘Pareto Principle’(also known as 80-20 rule), 80% of the bugs can be identified on 20% of the modules.
Pesticide paradox: When the tester identifies any defective module it is necessary to concentrate more on it by testing it with different combinations of valid and invalid input strings. After some testing iterations, the code standard will improve when the developers fix these issues. But, in some cases, there is a probability for new errors to be found. This is pesticide paradox. The only method to prevent this is revising and updating test cases on each iteration of software testing.
Testing is context-dependent: Different methods, procedures and testing types are available for detecting errors in software. But, it is not possible to randomly perform any one of the testings on a software/website and announce it to be error-free. Testing will depend mainly on the context of the domain that the application works. A banking-related software needs more testing compared to any travel & tourism website.
Absence of error – the fallacy: With continuous efforts, the tester can eliminate 99% of the errors before its deployment stage. But, all the efforts of the tester can be in vain, if the tester tests it for wrong requirements or if the output is not as predicted for the end-user. The time and effort spent on finding and fixing these defects will become useless in such situations.
