Error and Bug in Software Testing

1. Error/bug/defect/mistake are human intraction which produce an incorrect result.
Fault: Fault is a stage of software which is caused by an error/bug/defect/mistake.
Failure: It is a deviation of software from its expected delivery or service.
For eg.
you are driving a car and you are on road while on driving now there is two way on the road
a) left: mumbai
b) right: delhi
now you have to go to delhi it means you have to turn the stearing to the right, but by mistake you turn the stearing to the left, from that position that is called as "Error" because human intraction is there. and now Fault is there till you will not reach the mumbai, but when you reach mumbai that is a final stage which is called "Failure" becoz you had to reach delhi but now you are in Mumbai.
2. Differences in terms
a. Error: the mistakes made by developer in coding.
b. Bug: Found problem in application By Tester

c. Defect: Found problem in application By Customer after release

Difference Between Bug, Error, Defect and Issue

a. Bug: A software bug is an error, flaw, mistake, failure, or fault in a program that prevents it from behaving as intended (e.g., producing an incorrect result). Most bugs arise from mistakes and errors made by people in either a program's source code or its design, and a few are caused by compilers producing incorrect code.

b. Error: The mistake made by developer in coding.

c. Defect: Defect is something which is in the requirement document and it is not implemented or it is implemented in a wrong way.

d. Issue: Issue is something which is not all above, Some issues are there like site is slow, session related problems, security problems etc.

Related Testing Topic

a. Black Box testing


  1. Dude thanks for explaining Error/bug/defect/mistake with proper example. keep it up!