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📖 What is Defect (Bug)?

A defect is an imperfection or deficiency in a work product where it does not meet its requirements or specifications. If executed, a defect may cause a failure in the system.

🥋 Sensei Says:

"Remember the chain: Error (human mistake) -> Defect (bug in code) -> Failure (observable issue during execution). You need to know this sequence!"

📚 Certification: Certified Tester Foundation Level (CTFL-v4.0)

🔑 What are the Key Concepts of Defect (Bug)?

▸ Error vs Defect vs Failure
▸ Defect density
▸ Impact of defects

🎯 How does Defect (Bug) appear on the CTFL-v4.0 Exam?

Identifying the difference between an error made by a developer and the resulting defect in the code.

Understanding that a defect only causes a failure if executed.

❓ Frequently Asked Questions

Does every defect lead to a failure?

No, a defect must be executed under specific conditions to manifest as an observable failure.

What causes a defect?

Defects are caused by errors (mistakes) made by human beings during the software development process.

Related Terms from Certified Tester Foundation Level

Iterative Development Model Use Case Testing Experience-Based Testing Technique Product Risk Functional Testing Absence-of-Errors Fallacy

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