What is software testing and why we test

Software testing is the practice of checking that software behaves the way it should, and finding out where it does not. But that short definition hides a deeper idea worth getting right from the start.

Testing is about information 💡

The real purpose of testing is not to "prove the software works". It is to provide information about quality and risk so that people can make informed decisions. Should we release? Is this feature safe? What might break?

A tester's job is to reduce uncertainty. You explore how the software behaves, gather evidence, and report it clearly, so the team decides with eyes open instead of hoping for the best.

Why we test 🔍

Software is built by people, and people make mistakes. A misunderstanding in a requirement, a typo in a condition, or a forgotten edge case can all become a defect. Testing helps because it:

• Finds defects before users do
• Builds confidence that important flows work
• Documents how the system is expected to behave
• Reduces the risk and cost of failures in production

A quick vocabulary check 📖

Three words often get mixed up:

• Error (mistake): a human action that produces an incorrect result, like a developer misreading a rule.
• Defect (bug): the flaw in the code or document that the mistake introduced.
• Failure: what happens when a defect is triggered and the system behaves incorrectly.

A mistake leads to a defect, and a defect may lead to a failure when the right conditions occur.

Verification vs validation ✅

These two are the classic pair, and knowing the difference marks you as someone who understands testing:

• Verification asks: "Are we building the product right?" Does it match the specification, the design, and the requirements?
• Validation asks: "Are we building the right product?" Does it actually meet the real needs of its users?

You can build something that perfectly matches a specification (verification passes) and still fails to solve the user's real problem (validation fails). Good testing keeps an eye on both.

Exercise 🎯

Think of an app you use often. Write down one thing you would verify (does it match what it promises?) and one thing you would validate (does it truly serve the user's need?). Notice how they are different questions.

Suggested content 📚

• ISTQB Glossary

👨‍🏫 Remember the core idea: testing informs. It cannot prove there are no bugs, but it can tell you a great deal about the risk you are taking.

Show the world what you learned 🌎

To show your professional network what you have learned in this lesson, post the following on LinkedIn.

I am taking the "Software Testing Fundamentals" course by @Walmyr Lima e Silva Filho at the @Talking About Testing School, where I learned what software testing really is: providing information about quality and risk, and the difference between verification and validation. #TalkingAboutTesting #TATSchool #SoftwareTestingFundamentals #Testing #QualityAssurance

👨‍🏫 Remember to tag me in your post. Here is my LinkedIn profile.