“A mistake in coding is called error ,error found by the tester is called defect, defect accepted by development team then it is called bug , the build does not meet the requirements then it Is failure.”
Error : Human makes the error. It represents the mistake made by people. In other words, the software execution is in a state such that further processing will lead to failure.
Fault : Fault is incorrect step, process or data definition in a computer program which causes the program to behave in an unintended or unanticipated manner. It is the result of the error.
Defect : A defect is an error in coding or logic that causes a program to malfunction or to produce incorrect/unexpected results. Hence, any deviation from the specification mentioned in the product functional specification document is a defect.
Bug : Bug is a fault in the program which causes the program to behave in an unintended or unanticipated manner.