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Exact difference bet Bug, Error & Defect?

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Question by satya
Submitted on 2/2/2004
Related FAQ: comp.software.testing Frequently Asked Questions (FAQ)
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Exact difference bet Bug, Error & Defect?


Answer by bondy
Submitted on 2/9/2004
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I would venture that there is not really any difference. However, when I've been in more formal environments, "defect" was preferred over "bug." And personally, I think of an "error" as something generated by the software, and not as a defect/bug.

 

Answer by gfhgv
Submitted on 2/10/2004
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cgcgcgcgbc cfgfcgcfhbcfhdfrcyx ettrtrtg

 

Answer by Praveen A.H.
Submitted on 3/12/2004
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Bug or defect
   Any fault in the product is called defect or bug

Error
   It the one which is generated because of wrong login,loop or due to syntax

 

Answer by Gomes
Submitted on 3/15/2004
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Error : Is an undesirable deviation from requirements

Bug : Is an error found BEFORE the application goes into production

Defect :Is an error found AFTER the application goes into production

 

Answer by Murali
Submitted on 4/19/2004
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Error: The difference between Expected & Actual Outputs/Results
Bug: A programming error that causes a program to work poorly, produce incorrect results, or crash...........An error in software or hardware that causes a program to malfunction

 

Answer by sorted
Submitted on 5/3/2004
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They are one and the same. The issue is whether to call them bugs or defects.

The name "bug" gives off a subliminal impression that somehow the defect crawled into the code quite independantly of the software engineer.

The name "defect" presents the cold harsh reality that the engineer, analyst or designer actually got something wrong.

In my experience, Software Professionals have a strong preference for the word "bug". Yet in most other engineering disciplines the word defect is used.

 

Answer by YSurendraKumar
Submitted on 5/5/2004
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Error : Deviation for actual and the expected/theoritical value .

Bug : An Error found in the development environment before the product is shipped to the customer .

Defect : An Error found in the product itself after it is shipped to the customer .

 

Answer by nidheesh
Submitted on 5/8/2004
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In my perspective both defect and bug is same.
A defect can be defined as a variance from expectations.That is we can say that a bug in the code

 

Answer by KrishnaKishore
Submitted on 5/18/2004
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Defect: deviation of the customer requirement

bug   :to identifies the error change customer requirement

error: error means to change the functionality
of the program

 

Answer by rajkumar
Submitted on 6/3/2004
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Hi Everybody,

Hmm my wife was asked the same question..very conveniently she asked me.
gave her the same answers as
Answered by Praveen A.H.



 

Answer by venkat
Submitted on 6/15/2004
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error means normaly arised in software
In software testing if any errors found b tester/customer reported to devloper, then error accepted b devloper is called defect and accepted by devloper is called bug

 

Answer by shyam
Submitted on 6/21/2004
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Defect is the difference between expected and actual result.In the context of testing
Error,Defect and Bug are more or less the same.

 

Answer by Sudhi
Submitted on 8/3/2004
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Defect: The flaws that exist in the system and is in the knowledge of everyone and cannot be solved at that moment.

Bug: The flaws that exist in the system and the system doesn't work according to the business logic and occurs due to improper understanding of the requirements.

Error: The flaws that exist due to improper coding and it mainly involves syntactical errors like null pointer exception in the perspective of java

 

Answer by Sree Rama Krishna.K.V.P.
Submitted on 8/6/2004
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Error: Error is the difference between the expected and Actual Results.

Defect: A Defect is a deviation from specifications or what ever the things that made customer dissatisfaction.

Bug: A bug can be defined as a defect or fault in the system.
                  or
The unexpected behavior of an application is also called a Bug


 

Answer by Rohan Bangera
Submitted on 8/6/2004
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error: Undesirable output whicuh negates the requirement.

Bug : Any fault in the software that  is detected before the application is released

Defect : any fault or error in the software that is detected after the application is released

 

Answer by lavan
Submitted on 8/24/2004
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BUG- WE UNDESTOOD THAT ONE WRONGLY AND DONE THE MISTAKE I.E BY USING SRS

DEFECT- IN SRS ONLY WRONG , MEANS THAT PERSON WRONGLY UNDERSTOOD THE CUSTOMER REQUIREMENT , BUT WE WILL DONE THAT ONE CORRECTLY OK.

 

Answer by ani raj
Submitted on 8/30/2004
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above all answers are wrong

 

Answer by Srinivas Undrakonda
Submitted on 9/2/2004
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BUG: Un Expected Behaviour Found in Development/QA Environment before product released to Customer.
DEFECT:Same as BUG but found in realtime environment/at customer's site.
ERROR: Any thing that is not comfirming to requirements/expected behaviour and it may be at any stage like during Development/QA or even after release of product. i.e. An Error can be a Ddefect or Bug.

 

Answer by ariv
Submitted on 9/3/2004
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bugs are nothing but an appearance of defect.That is defect is an error in product without evidence of existence.After a defect is identified it is called a bug.
Defects are  also called hidden bugs.

 

Answer by Neeraj Sharma
Submitted on 9/15/2004
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hi,

i am agree with the Praveen A.H. answer

 

Answer by Vishal Kharge
Submitted on 9/28/2004
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Bug : Is an error found BEFORE the application goes into production

Defect :Is an error found AFTER the application goes into production

 

Answer by BSH
Submitted on 9/29/2004
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A bug is a fault found  before the product is released to a client and a defect is a fault that is detected after the product is released.

An error is any discrepancy between the expected value and the actually observed value.

 

Answer by bala
Submitted on 10/1/2004
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What is Difference between Bug and Defect?
I want exact definition.

 

Answer by Saint
Submitted on 10/4/2004
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Error : Deviation for actual, the expected/theoritical value and also the syntax

Bug : An Error found in the product itself after it is shipped to the customer or may be some new failure encounter with manipulation of data.

Defect : An Error found in the development environment before the product is shipped to the customer .

 

Answer by Pradeep Kumar chouhan.
Submitted on 10/6/2004
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During the Testing cycle -

If we found any abnormal beheviour of application the it's a bug

But if the bug is not found in that testing cycle and found in the next cycle of testing, then its a defect.

Deviation for actual and the expected/theoritical value .

 

Answer by Sachin bora
Submitted on 10/28/2004
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I would venture that there is not really any difference. However, when I've been in more formal environments, "defect" was preferred over "bug." And personally, I think of an "error" as something generated by the software, and not as a defect/bug.

Bug or defect
   Any fault in the product is called defect or bug

Error
   It the one which is generated because of wrong login,loop or due to syntax

Bug : Is an error found BEFORE the application goes into production

Defect :Is an error found AFTER the application goes into production
Error: The difference between Expected & Actual Outputs/Results
Bug: A programming error that causes a program to work poorly, produce incorrect results, or crash...........An error in software or hardware that causes a program to malfunction

They are one and the same. The issue is whether to call them bugs or defects.

The name "bug" gives off a subliminal impression that somehow the defect crawled into the code quite independantly of the software engineer.

The name "defect" presents the cold harsh reality that the engineer, analyst or designer actually got something wrong.

In my experience, Software Professionals have a strong preference for the word "bug". Yet in most other engineering disciplines the word defect is used.

Bug : An Error found in the development environment before the product is shipped to the customer .

Defect : An Error found in the product itself after it is shipped to the customer .

Defect: deviation of the customer requirement

bug   :to identifies the error change customer requirement

 

Answer by Naseer
Submitted on 11/5/2004
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Error can be defined as : the occurrence of an incorrect result produced by a System/Software.

Bug can be defined as :A software or hardware error that causes the system to malfunction or to function improperly.
Error or bug almost same.

Defect:Anything that does not conform to the product's specifications, is a defect. Error or Bug makes defect to occur in system/Software.

 

Answer by sankar
Submitted on 11/9/2004
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If system gives an wrong output,with some relation with the logic of the system it is a bug.
If a system does not give an output it is a defect.
If system gives an wrong output,without any relation with the logic of the system it is a error.

 

Answer by Uday, Arun, Kartheek
Submitted on 11/22/2004
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This is very good question with respect to s/w testing-

Error : Error occurs in the syntax level (syntax error) or it could be in environment, application and the resource associated with testing bed setup.

Defect : Defect results when there is a deviation from the requirement/wrong implementation of requirements leads to defect.

Bug: Bug results due to developers improper coding in the application.

 

Answer by SIDDHU
Submitted on 12/6/2004
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Bug   : I software which does not meet the Software Req Spec (SRS) is said to contain abug.

Defect  : A defect is a nonconfirmation to quality which has no mention is SRS

A program can have defects but cant have bugs

A bug or a defect surfaces itself in the form of an error

 

Answer by ArijitD
Submitted on 1/4/2005
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Bug:- Deviation from expected result.

Defect:- Problems in the algorithm leads to failure.

 

Answer by ilango
Submitted on 1/27/2005
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Bugs : It is the term used between the developers and the testers. If some deviation present from the expected result, its called as bugs.
Defect : It is the term used in the Quality perspective.Defects can also be the term used after the software goes to production.

 

Answer by Saluja
Submitted on 2/3/2005
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Error:That is deviated from Customer Requirement.
Bug:Error Found By Tester while Testing the Application.
Defect:Error Found  By the Customer After delivering the Project


 

Answer by Abu
Submitted on 2/4/2005
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A defect is for something that normally works, but it has something out-of-spec.

A bug exists because what is supposed to work does not work as what you


 

Answer by sushil
Submitted on 2/16/2005
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when developer found difference between actual and expected result then it is error and if found by tester then it is bug defect is same as described by y surendra kumar

 

Answer by pandiarajan
Submitted on 4/2/2005
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Error - Mistake in program (Eg : Syntax error and Logical error)

Bug - Deviation from expected result in an application

Defect - mistake in algorithm

 

Answer by Chandu
Submitted on 5/2/2005
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ERROR:A mistake in coding is called ERROR.
DEFECT:When Tester find there mistakes as mismatches between Expected and actual is called DEFECT.
BUG:When the defects are accepted by developers to be resolved is called BUG

TESTERS are calling as DEFECTS.
DEVELOPERS are calling as BUG.

 

Answer by zameer
Submitted on 5/7/2005
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defect is a defect in the documentation and bug is a mistake in the application

 

Answer by mahesh
Submitted on 5/10/2005
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Error: programmatically mistake leads to error.
Bug: Deviation from the expected result.
Defect: Problem in algorithm leads to failure.

 

Answer by sudheer
Submitted on 5/19/2005
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error -- deviation of code in programme shown by compiler or interpretter.
defect -- found by the test engg, while executing the .exe or project.
bug -- only when devloper accepts ur defect
then it is said to be as bu.

 

Answer by Mafia
Submitted on 5/24/2005
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Refer any SW Eng book

 

Answer by chaitu
Submitted on 6/7/2005
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Bug is a mistake made by the developer and found by the tester.
Error is made by tester and found by the client.

 

Answer by Prashanth Hospattan
Submitted on 6/24/2005
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erroris one which does not have weightage where as bug is one which has more weightage.

error is the problem occured while executing a program or function or module to ensure that program working as per the specification. it has little scope compared to bug

bug is the error occured while executing the entire application to ensure whether the application confromance with the requirements specified by the client.
defect is error in the delivered product.

 

Answer by LACUNAG
Submitted on 7/4/2005
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BUG : THE DISSATISFIED REQUIREMENT IS CALLED A BUG
DEFECT : MISSING REQUIREMENT IS CALLED A DEFECT
ERROR :IT CAN BE ANYTHING IN GENERAL...

EXAMPLE : IF A PEN IS BOUGHT...
DEFECT IS :IT HAS ALL THE FEATURES BUT DOES'NT WRITE AT ALL.
BUG IS :IT HAS ALL THE FEATURES AND IT WRITES, BUT  NOT PROPERLY...

 

Answer by Gums
Submitted on 7/11/2005
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Error: programmatically mistake leads to error.
Bug: Deviation from the expected result.
Defect: Problem in algorithm leads to failure.

 

Answer by Kiran
Submitted on 7/20/2005
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Error,Bug and Defect are more or less the same, but there is slight difference among them.
Error:Deviation from the Actual\Expected results and also Deviation from the requirements.
Bug:An error occurred before the shipment of the product,(Generally called by Testers)
Defect:An error occurred after the shipment of the product.(Generally called by Developers)

 

Answer by Sushil Dwivedi
Submitted on 8/3/2005
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  I think they r Same But Minor Diffirence Between Them.

Error-- Error gives diffirence between Actual O/p and Expected O/p.If Error comes into apllication then no any further application process will enable.
Defect/Bug - Defect can any logical mistake of Developer/Designer.If the Bug present into the Application then Application will run But it will not give the correct O/p.

For eg--  If we see the functionality of the Ok button . When we press Ok Button we want open XX page but open YY page then this is Defect But If Any Red Type message comes into the screen then It is Error

 

Answer by sam
Submitted on 8/9/2005
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not much different

 

Answer by Pranit
Submitted on 8/20/2005
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Bug is something that was considered but not implemented, for whatever reasons.A bug exists because what is supposed to work does not work as what you expected.
A defect is for something that normally works, but it has something out-of-spec. Defects occur usually when a product no longer works the way it used to.

 

Answer by navdeep
Submitted on 9/2/2005
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Bug- A fault in a program which causes the program to perform in an unintended or unanticipated manner.

Defect - If software misses some feature or function from what is there in requirement it is called as defect.

 

Answer by Sathyajithvk
Submitted on 9/3/2005
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Error:     Generally Its a human mistake. In s/ws While the development (coding) its occure.Its may be syntax error, logical error or symantic error. So while coding phase its an Error.

Bug:       Testing is the process of executing a program with the intent of finding erros.After finding an error on Testing stage its called as bug.

Defect:
           After finding a bug, while reporting stage its called as a defect. If the defect ratio is more than 50% in s/ws, then we have to rebuild/redevelope the total software.

 

Answer by Venkat
Submitted on 9/16/2005
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Error: is a result of verification process. The term error is a part of Static testing.
Bug: is a problem found in the application before delivering it to the customer.
Defect: is a problem found in the application after delivering it to the customer.

 

Answer by GOPi
Submitted on 9/23/2005
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Defect: It is the difference between the Expected result & Observed
result

Bug: It is the condition that makes the system unable to do what it is
expected to do.

Error: It is the inability of the system to meet its expectations. eg)
When a system crashes & data is lost.

 

Answer by person x
Submitted on 9/23/2005
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An error is generated because of wrong logic,loops and syntax.

But a bug is generating due to more than one error.

A defect can be defined as a variance from expectations or something found after the release of a product .

 

Answer by balaji
Submitted on 9/29/2005
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error:human mistakes
bug:any functionality performed by the system which is not supposed to be performed is called a bug.
defect:deviation from the expected value is called defect

 

Answer by Subramani
Submitted on 10/17/2005
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Bug:Word Used by

 

Answer by Praveen Patha
Submitted on 11/6/2005
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Defect is the one which deviates from the requirements, deviation from the requirements is Defect.

Bug can be called as a defect.

Error is the one which is thown when development(coding) is done, might be wrong in syntax or wrong in logic.

 

Answer by krishna ranjit
Submitted on 11/8/2005
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bug: happens or occurs without the knowledge of developer

defect : bug leads to a defect in the product or project

 

Answer by revaks
Submitted on 11/18/2005
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Error: The variation from the requirements that occurs in coding stage.
Bug: The variation from the requirements that is found out by a tester
Defect: The variation that is found out by the client during the implementation stage

 

Answer by tushar
Submitted on 11/24/2005
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Error: is a fault found by the developer on developement site.

Bug: is a fault found by the end user or customer on customer site.

defect: no idea

 

Answer by raja
Submitted on 12/14/2005
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Error :error due to mistakes in syntax or unhandled exceptions
Ex: Special chars in text field or Failed in boundary value analysis,....

Bug :wrong logic or algorithm it will not give any error but shows Difference between actual and expected results and it will replicate N times.

Ex : Rounding values like $2.55 to 2.6 here its showing $.05 more.

 

Answer by raja
Submitted on 12/14/2005
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Error :error due to mistakes in syntax or unhandled exceptions
Ex: Special chars in text field or Failed in boundary value analysis,....

Bug :wrong logic or algorithm it will not give any error but shows Difference between actual and expected results and it will replicate N times.

Ex : Rounding values like $2.55 to 2.6 here its showing $.05 more.

 

Answer by akhilesh
Submitted on 12/23/2005
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error buds defects nothing but same i can identify that
error means actual real product and expected

bugs  programming error are known as bugs

defect error found when product have been deliverd.

 

Answer by Faten Ahmed EL_Gamal
Submitted on 12/24/2005
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* Error is the syntax error can be discovered during compilation time
*Bug is an error in the logic that cannot be discovered by the compiler

 

Answer by Amit Chhabra
Submitted on 12/26/2005
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Bug:- Programmatical Error.
Error:- Diff(Standard output-Actual Output)

 

Answer by GPathan
Submitted on 12/26/2005
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An error is incorrectly written code, usually not intentional.
BUGS.
******
A persistent error in software or hardware. If the bug is in software, it can be corrected by changing the program. If the bug is in hardware, new circuits have to be designed.


 

Answer by a
Submitted on 12/28/2005
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Bug:- Difference between

 

Answer by Tarun Wadhwa (Pta).
Submitted on 12/28/2005
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Bug:- Difference between the expected and actual result,this term used by tester not by programmer.

Error:- Programming error which produces an incorrect result(syntax error, logical error etc).This term is used by programmer not by tester.

Defect:- something(Not any error message ,server crash etc) is coming on client side which does not match with specification given.This term is used by client not by tester or programmer.

Fault:- When client check and something wrong(server error,some other error message etc) is coming ,This term used on client side not on tester or programmer side.

Failure:- When client check and something wrong is coming ,As a result of which client cant perform further or application stop.This term is used on client side not by tester or programmer .

 

Answer by Manohar
Submitted on 1/1/2006
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Defect:- The Misinterpretation in Requirements / Design specification / Architecture is called as Defect
Bug: - The Deviation in Functionality from actual Functionality during SIT /Application / Coding testing is called as Bug.

 

Answer by G ThyagaRaju
Submitted on 1/3/2006
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Error: These are the quality problem discovered by the software Engineers before the product is released to the End-Users

Defect: Error that are uncovered by the Software Engineers becomes defects at the End user

 

Answer by gfhgh
Submitted on 1/9/2006
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,mojiu9 uhjf k kjk loi

 

Answer by swapna
Submitted on 1/10/2006
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ERROR: IT IS A DEVIATION FOR ACTUAL AND EXPECTED VALUE

BUG: IT IS AN ERROR CAUSED AT TIME OF PRODUCTION. IT MAY LEAD TO UNEXPECTED RESULTS AND THEY CAN BE FIXED

DEFECT: IT IS AN ERROR CAUSED AFTER DELIVERING THE PRODUCT TO CLIENT


 

Answer by swapna
Submitted on 1/10/2006
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ERROR: IT IS A DEVIATION FOR ACTUAL AND EXPECTED VALUE

BUG: IT IS AN ERROR CAUSED AT TIME OF PRODUCTION. IT MAY LEAD TO UNEXPECTED RESULTS AND THEY CAN BE FIXED

DEFECT: IT IS AN ERROR CAUSED AFTER DELIVERING THE PRODUCT TO CLIENT


 

Answer by testing
Submitted on 2/17/2006
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error: amount by which result is incorrect.
defect:flow in work product
bug: defect

 

Answer by Sathyajith V K
Submitted on 2/21/2006
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Error--> Human mistake , usually while coding..

Bug--> Error getting while  AUT..

Defect--> When the Bug is reported and accepted ,we call it as defect..

If defect ratio is more than 50% we have to do reverse engineering !!

 

Answer by Prasanna
Submitted on 3/13/2006
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1.when you buying a shirt you find that contains small whole..like this Any fault in the product is called defect

2.If you are doing one operation it do some other operation is called Bug.

3.Deviation from normal is called Error.

 

Answer by Pazhani
Submitted on 4/3/2006
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asdfsadfsadfsad

 

Answer by Arvindarr D Kangg
Submitted on 4/7/2006
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Bug: If it does something which is not mentioned in the spec.
Error:Human mistake.
Defect:Deviation from the requirement

 

Answer by Arvindarr D Kangg
Submitted on 4/7/2006
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Bug: If it does something which is not mentioned in the spec.
Error:Human mistake.
Defect:Deviation from the requirement

 

Answer by saurabh tripathi
Submitted on 4/11/2006
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correct answer is
hfeuhf jfgfgv kokwgvk, jiwjf,m
gvgrlk
  gjgkjkg

thks

 

Answer by Param
Submitted on 4/18/2006
Rating: Not yet rated Rate this answer: