What is Bug defect error and failure

So, in this paper, we are going to learn about What is Bug defect error and failure in detail. We will first see the definition of the same and the differences between the Bug, defect, error, and failure. Let start.

 

🔹What is Error?

Definition:
An error is a mistake made by a developer or tester in understanding, coding, designing, or interpreting requirements.

• Example: A developer writes a = b + c instead of a = b - c.

• When it happens: During design, coding, or even requirements gathering.

• Also known as: Mistake or fault in some contexts.

🔹 What is Defect?

Definition:
A defect is an issue or flaw in the software code, design, or logic that prevents the program from working correctly.
It is caused by an error.

• Example: A button on a form doesn’t work because the developer forgot to link it to a function.

• Detected during: Development or testing phase.

• Also known as: Bug.

🔹 What is Bug?

Definition:
A bug is an informal term used to describe a defect found in the software during testing or after deployment.

• Example: An app crashes when you tap a specific icon.

• Note: Bugs are what testers usually report.

🔹What is Failure?

Definition:
A failure is the inability of a software system or component to perform its required functions within specified performance requirements during execution. It happens when a defect is triggered during use.

• Example: The app freezes or gives wrong output to the user.

• Caused by: A defect or bug being triggered during actual use.

• Visible to: End users.

 

Term	Where It Happens	Who Causes/Sees It	Description
Error	In design/code	Developer	A human mistake
Defect	In the software	Found during testing	A flaw in the code
Bug	In the software	Found by testers/users	Informal name for a defect
Failure	During execution	End user	Software doesn’t work as expected

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