Software testing is the process of evaluating and verifying that a software product or application does what it is supposed to do. The benefits of testing include preventing bugs, reducing development costs and improving performance.
There are many different types of software tests, each with specific objectives and strategies:
In each case, validating base requirements is a critical assessment. Just as important, exploratory testing helps a tester or testing team uncover hard-to-predict scenarios and situations that can lead to software errors.
Even a simple application can be subject to a large number and variety of tests. A test management plan helps to prioritize which types of testing provide the most value – given available time and resources. Testing effectiveness is optimized by running the fewest number of tests to find the largest number of defects.
Software testing arrived alongside the development of software, which had its beginnings just after the second world war. Computer scientist Tom Kilburn is credited with writing the first piece of software, which debuted on June 21, 1948, at the University of Manchester in England. It performed mathematical calculations using machine code instructions.
Debugging was the main testing method at the time and remained so for the next two decades. By the 1980s, development teams looked beyond isolating and fixing software bugs to testing applications in real-world settings. It set the stage for a broader view of testing, which encompassed a quality assurance process that was part of the software development life cycle.
“In the 1990s, there was a transition from testing to a more comprehensive process called quality assurance, which covers the entire software development cycle and affects the processes of planning, design, creation and execution of test cases, support for existing test cases and test environments,” says Alexander Yaroshko in his post on the uTest developer site.
“Testing had reached a qualitatively new level, which led to the further development of methodologies, the emergence of powerful tools for managing the testing process and test automation tools.” 1
Software testing has traditionally been separated from the rest of development. It is often conducted later in the software development life cycle after the product build or execution stage. A tester may only have a small window to test the code – sometimes just before the application goes to market. If defects are found, there may be little time for recoding or retesting. It is not uncommon to release software on time, but with bugs and fixes needed. Or a testing team may fix errors but miss a release date.
Doing test activities earlier in the cycle helps keep the testing effort at the forefront rather than as an afterthought to development. Earlier software tests also mean that defects are less expensive to resolve.
Many development teams now use a methodology known as continuous testing. It is part of a DevOps approach – where development and operations collaborate over the entire product life cycle. The aim is to accelerate software delivery while balancing cost, quality and risk. With this testing technique, teams don’t need to wait for the software to be built before testing starts. They can run tests much earlier in the cycle to discover defects sooner, when they are easier to fix.
Few can argue against the need for quality control when developing software. Late delivery or software defects can damage a brand’s reputation — leading to frustrated and lost customers. In extreme cases, a bug or defect can degrade interconnected systems or cause serious malfunctions.
Consider Nissan having to recall over 1 million cars due to a software defect in the airbag sensor detectors. Or a software bug that caused the failure of a USD 1.2 billion military satellite launch. 2 The numbers speak for themselves. Software failures in the US cost the economy USD 1.1 trillion in assets in 2016. What’s more, they impacted 4.4 billion customers. 3
Though testing itself costs money, companies can save millions per year in development and support if they have a good testing technique and QA processes in place. Early software testing uncovers problems before a product goes to market. The sooner development teams receive test feedback, the sooner they can address issues such as:
When development leaves ample room for testing, it improves software reliability and high-quality applications are delivered with few errors. A system that meets or even exceeds customer expectations leads to potentially more sales and greater market share.
Software testing follows a common process. Tasks or steps include defining the test environment, developing test cases, writing scripts, analyzing test results and submitting defect reports.
Testing can be time-consuming. Manual testing or ad-hoc testing may be enough for small builds. However, for larger systems, tools are frequently used to automate tasks. Automated testing helps teams implement different scenarios, test differentiators (such as moving components into a cloud environment), and quickly get feedback on what works and what doesn't.
A good testing approach encompasses the application programming interface (API), user interface and system levels. As well, the more tests that are automated, and run early, the better. Some teams build in-house test automation tools. However, vendor solutions offer features that can streamline key test management tasks such as:
IBM Rational Test Workbench provides software testing tools to support a DevOps approach: API testing, functional UI testing, performance testing and service virtualization.
IBM Rational Test Virtualization Server software enables early and frequent testing in the development lifecycle.
IBM Rational Performance Tester helps software testing teams test earlier and more frequently as part of a DevOps approach.
Use one tool to collaborate across teams, manage code, run standup meetings, plan sprints and track work. Available on premises and on the cloud.
IBM Rational ClearCase provides controlled access to software assets, including code, requirements, design documents, models, test plans and test results.
IBM Engineering Test Management is a collaborative, quality management solution that offers end-to-end test planning and test asset management, from requirements to defects.
1 https://www.utest.com/articles/small-history-of-software-testing (link resides outside of ibm.com)
2 https://www.guru99.com/software-testing-introduction-importance.html (link resides outside of ibm.com)
3 https://www.cloudcomputing-news.net/news/2017/oct/30/glitch-economy-counting-cost-software-failures/ (link resides outside of ibm.com)