assume that you have given valid user name, invalid password and clicked on Login Button, in return if application has accepted you user name and password, and Main window is displayed
Then this is a functionality defect.
Usability Defects :
assume that you have given valid user name, invalid password and clicked on Login Button, in return if application has generated a validation message stating "Please enter valid user name" instead of "Please enter valid Password"
Then this is a Usability Defect.
Above answer was rated as good by the following members: mdadil
assume that you have given valid user name invalid password and clicked on Login Button in return if application has accepted you user name and password and Main window is displayed
Then this is a functionality defect.
Usability Defects :
assume that you have given valid user name invalid password and clicked on Login Button in return if application has generated a validation message stating "Please enter valid user name" instead of "Please enter valid Password"
Suppose if there is 2 Drop down list box (Country & State)in the form
Functional Defects: On Page load the application should load the Country items in the form after selecting the country in the list it should reload the page and the corresponding State should loaded and displayed in the State drop list box. if it is not loaded/displayed means it is Functional Defect.
Usability Defects: If the user changed the Countries and looks for the corresponding state if the drop down list unable to load again the State list. its a Functional and Usability Defect.
If the application is not behaving in the way as the requirements document suggests then it is considered as a functional defect. For example in a website say a nokia website if the spelling is Nokie then it is a usability defect which may not be listed in the requirement document but can be logged by the tester because of hs common sense. Also in order to log the usability defects the testers need not have specific test cases. They can log them while playing with the system.
Functional defect: If you given a login form having username and password and if you give the valid user name and password but it wont accepts means it is a functional defect.
Usability defect: The usability is how the application is user friendly to the customer. It depends on the front page of the application. It should be understandable to the customer. If the proper buttons or fields are not accessable by the customer is usability defect.
Functionality Defects: If anything is not working as per requirement then it is a functional defect.
Usability Defects: Any decrepencies in the look and feel of application is considered as usability defect.
E.g. Consider an requirement: Upon clicking "Register" button(color of button is red and in rounded shape) application will redirect to homepage of the application.
Functional Defect: If upon clicking "Register" button application is directed to login page instead of homepage then it is a functional defect.
Usability Defect: If label of the button is displayed as "regster" instead of "Register" and color is not "red" then this will be a usability defect.
Functional Defect : If software is not working as per requirement specified.
Example: Requiremnet:After successful login homepage should be logged in. Funtional Testing test case: Verify that when correct username and password is entered homepage is displayed. Expected Result : Home page should be displayed. Actual Result: Error message is prompted "Page cannot be displayed". Usability Defect : When a user does not find a software product understandable easy to learn easy to operate and attractive.
Example: Usability Testing test case: Verify that homepage should have a content in Japanese Language. Expected Result : Home page have a content in Japanese Language. Actual Result: Home page have a content in English Language
Functional defects entirely belongs to the applicational functionality failure defects where as usability defects belongs to the UI style font color wise ununiformness issues..
Functional Defect:- If the functionality of the application is not working as per the requirement specification it is functionality defect. e.g. For calculator application Requirement is 1+1 2. But the application is displaying 1+1 0. It is functionality defect.
Usability Defect:- If the application is not easy to use it is hard to use. User interface should be proper and easy to use to the user. e.g. User interface should be proper. Easy to use.
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