Software testing objectively evaluates a software component, or an entire software system, to assess one or more of its properties because bugs and other problems can be very costly (and even dangerous). This is an important process to help identify bugs, errors, gaps or any other missing requirements in the initial brief or customer specifications, if any.
Software testing can be done manually or using automated tools, or even a mixture of the two.
Why is software testing necessary?
Software testing is a great way, as we mentioned earlier, to identify product flaws before you launch it.
To drive the point home, here are some concrete examples of why proper software testing should be taken seriously.
- In April 2015, London Bloomberg Terminal crashed due to a software glitch. This affected hundreds of thousands of financial market traders. He even forced the British government to postpone a 3 billion pounds debt sale. With proper testing, this could have been avoided.
- Also in 2015, due to an unidentified software issue, Starbucks was forced to close 60% of its stores in the United States and Canada. Due to a problem during the daily system refresh of their point of sale system prevent the company from carrying out transactions. In some cases, Starbucks was forced to serve orders free.
- In February 1991, during the first Gulf War, an Iraqi missile struck the American base at Dhahran in Saudi Arabia, killing 28 American soldiers. Following an investigation, it was determined that the base’s anti-ballistic system failed to launch due to a computer bug. The internal clock had drifted by a few milliseconds per hour, which ultimately had a huge impact on the synchronization of the systems.
- Nissan was once obliged to call back a little less 1 million of its 2013 and 2014 Infiniti models on the market after the identification of a serious software bug, associated with its airbag sensors. This follows two crashes that ultimately led to the discovery of the issue.
- During the Falklands War in 1982, the Royal Navy destroyer, HMS Sheffield sank due to a software problem with her radar warning system. According to a report of the timewhile he was able to pick up the incoming Exocet anti-ship missile, he registered it as a “friend”, preventing the launch of countermeasures.
- Recently, the Boeing 737 Max 8 was grounded for software upgrades after two planes crashed in 2018. These software issues not only cost Boeing billions, but sadly also claimed the lives of hundreds of people.
If a proper testing regime had been in place, it is entirely possible that at least some of the above could have been avoided. But these errors are not easy to predict before they occur. As the saying goes, hindsight is 20:20.
What are the benefits of software testing?
As we have already seen, not testing the software to its breaking limits can have disastrous consequences. In addition, software testing also has very important and tangible benefits for developers.

These include, but are not limited to:
- Software testing is very profitable: This is probably the most important benefit of software testing. Testing any IT project in a timely manner helps you save money in the long run. This is especially true for spotting errors, bugs, and other issues early in the development cycle.
- Software testing helps improve security: Another extremely important benefit of testing is to ensure product safety, it pays dividends to the developer. This not only gives consumers confidence in the product, but it also helps plug holes in its defenses before hackers find them.
- Product quality: This is an essential requirement of any software product. Testing ensures that a quality product is delivered to customers.
- Client satisfaction: The main objective of any product is to satisfy its customers. UI/UX testing ensures the best user experience.
What are the different types of software testing?
Software testing is generally divided into three broad categories. These are, broadly:-
- Functional test
- Non-functional testing/performance testing
- Maintenance tests

Functional testing, as defined by Techopedia is “a software testing process used in software development in which software is tested to ensure that it conforms to all requirements. [It] is a means of checking the software to ensure that it has all the required functionality specified in its functional requirements.”
In a nutshell, functional testing is used to ensure that the software provides the same output required by the end user and the consumers.
Non-functional tests, on the other hand, is a form of software testing for evaluating non-functional aspects of software. These will usually be things like performance, usability, reliability, etc.
This form of testing is designed to test the readiness of a system, such as by non-functional parameters which are not normally processed by functional tests. A good example would be to check how many users can log in at a given time.
Maintenance testsunlike the previous two, is usually performed to identify potential equipment problems when, for example, migrating software from one piece of hardware to another.
It can also be used to check whether other hardware modifications, repairs or upgrades have affected software or not. Such software testing can be performed at the system, equipment, or component level, as needed.
From now on, we’ll explore some of the most common types of software testing that fall under these broad categories (with the exception of maintenance testing).

Trust us when we say this list is far from exhaustive. In fact, there are many more 150 different kinds of them, and more and more.
You should also note that the following list is not in any particular order, except that we have divided them into functional, non-functional, and maintenance-type software tests.
What types of functional software testing are there?
Here are some of the most common forms of functional software testing.
1. Integration testing
Integration testing is a form of software testing designed to verify all modules embedded in software. This usually happens after all component modules have been integrated together, hence the term.
Modules can generally consist of code modules, individual applications, client and server applications on a network, etc. This type of testing is particularly relevant for client/server and distributed systems.