software Testing/QA Interview Questions

Important Testing Interview Questions:

What is quality assurance?
Software QA involves the entire software development PROCESS - monitoring and improving the process, making sure that any agreed-upon standards and procedures are followed, and ensuring that problems are found and dealt with. It is oriented to 'prevention'.

What is the difference between QA and testing?
Testing involves operation of a system or application under controlled conditions and evaluating the results. It is oriented to 'detection'.
Software QA involves the entire software development PROCESS - monitoring and improving the process, making sure that any agreed-upon standards and procedures are followed, and ensuring that problems are found and dealt with. It is oriented to 'prevention'.

Describe the difference between validation and verification

Verification is done by frequent evaluation and meetings to appraise the documents, policy, code, requirements, and specifications. This is done with the checklists, walkthroughs, and inspection meetings.
Validation is done during actual testing and it takes place after all the verifications are being done.



What are SDLC and STLC ? Explain its different phases.
SDLC
Requirement phase
Designing phase (HLD, DLD (Program spec))
Coding
Testing
Release
Maintenance

STLC
System Study
Test planning
Writing Test case or scripts
Review the test case
Executing test case
Bug tracking
Report the defect


What is the difference between Bug, Error and Defect?

Error : It is the Deviation from actual and the expected value.
Bug : It is found in the development environment before the product is shipped to the respective customer.

Defect : It is found in the product itself after it is shipped to the respective customer.

What is Error guessing and Error seeding ?
Error Guessing is a test case design technique where the tester has to guess what faults might occur and to design the tests to represent them.
Error Seeding is the process of adding known faults intentionally in a program for the reason of monitoring the rate of detection & removal and also to estimate the number of faults remaining in the program.

What is Bug Life Cycle?
Bug Life Cycle is nothing but the various phases a Bug undergoes after it is raised or reported.
New or Opened
Assigned
Fixed
Tested
Closed

Explain Peer Review in Software Testing.

It is an alternative form of Testing, where some colleagues were invited to examine your work products for defects and improvement opportunities.
Some Peer review approaches are,
Inspection – It is a more systematic and rigorous type of peer review. Inspections are more effective at finding defects than are informal reviews.
Ex : In Motorola’s Iridium project nearly 80% of the defects were detected through inspections where only 60% of the defects were detected through informal reviews.
Team Reviews – It is a planned and structured approach but less formal and less rigorous comparing to Inspections.
Walkthrough – It is an informal review because the work product’s author describes it to some colleagues and asks for suggestions. Walkthroughs are informal because they typically do not follow a defined procedure, do not specify exit criteria, require no management reporting, and generate no metrics.
Pair Programming – In Pair Programming, two developers work together on the same program at a single workstation and continuously reviewing their work.
Peer Deskcheck – In Peer Deskcheck only one person besides the author examines the work product. It is an informal review, where the reviewer can use defect checklists and some analysis methods to increase the effectiveness.


What is Traceability Matrix ?
Traceability Matrix is a document used for tracking the requirement, Test cases and the defect. This document is prepared to make the clients satisfy that the coverage done is complete as end to end, This document consists of Requirement/Base line doc Ref No., Test case/Condition, Defects/Bug id. Using this document the person can track the Requirement based on the Defect id.

Boundary value testing
It is a technique to find whether the application is accepting the expected range of values and rejecting the values which falls out of range.
Ex. A user ID text box has to accept alphabet characters ( a-z ) with length of 4 to 10 characters.
BVA is done like this, max value:10 pass; max-1: 9 pass;
max+1=11 fail ;min=4 pass;min+1=5 pass;min-1=3 fail;
Like wise we check the corner values and come out with a conclusion whether the application is accepting correct range of values.

Equivalence testing
It is normally used to check the type of the object.
Ex. A user ID text box has to accept alphabet characters ( a - z ) with length of 4 to 10 characters.
In +ve condition we have test the object by giving alphabets. i.e a-z char only, after that we need to check whether the object accepts the value, it will pass.
In -ve condition we have to test by giving other than alphabets (a-z) i.e A-Z,0-9,blank etc, it will fail.

What is Defect Leakage ?
Defect leakage occurs at the Customer or the End user side after the application delivery. After the release of the application to the client, if the end user gets any type of defects by using that application then it is called as Defect leakage. This Defect Leakage is also called as Bug Leak.

What is Bidirectional Traceability ?
Bidirectional Traceability must be implemented from both forward & backward(i.e from requirements to end products and from end products to requirements) When the the requirements are fully managed then traceability should be established between source requirements to its lower level requirements and from lower level requirements to source. This helps us to determine all the source requirements have been completely addressed.

What is Buffer Overflow?
A buffer overflow occurs when a program or process tries to store more data in a buffer (temporary data storage area) than it was intended to hold. Since buffers are created to contain a finite amount of data, the extra information - which has to go somewhere - can overflow into adjacent buffers, corrupting or overwriting the valid data held in them


What is a Memory Leak?
A memory leak occurs when a programmer dynamically allocates memory space for a variable of some type, but then fails to free up that space before the program completes. This leaves less free memory for the system to use. Repeated running of the program or function that causes such memory loss can eventually crash the system or result in a denial of service.


What is 'configuration management'?
Configuration management is a process to control and document any changes made during the life of a project. Revision control, Change Control, and Release Control are important aspects of Configuration Management.

For Web Applications what type of tests are you going to do?
Web-based applications present new challenges, these challenges include:
- Short release cycles;
- Constantly Changing Technology;
- Possible huge number of users during initial website launch;
- Inability to control the user's running environment;
- 24-hour availability of the web site.

The following are the techniques used for web application testing.
1. Functionality Testing
Functionality testing involves making Sure the features that most affect user interactions work properly. These include:
· forms
· searches
· pop-up windows
· shopping carts
· online payments

2. Usability Testing
Many users have low tolerance for anything that is difficult to use or that does not work. A user's first impression of the site is important, and many websites have become cluttered with an increasing number of features. For general-use websites frustrated users can easily click over a competitor's site.

Usability testing involves following main steps
· identify the website's purpose;
· identify the indented users ;
· define tests and conduct the usability testing
· analyze the acquired information

3. Navigation Testing
Good Navigation is an essential part of a website, especially those that are complex and provide a lot of information. Assessing navigation is a major part of usability Testing.

4. Forms Testing
Websites that use forms need tests to ensure that each field works properly and that the forms posts all data as intended by the designer.

5. Page Content Testing
Each web page must be tested for correct content from the user perspective for correct content from the user perspective. These tests fall into two categories: ensuring that each component functions correctly and ensuring that the content of each is correct.

6. Configuration and Compatibility testing
A key challenge for web applications is ensuring that the user sees a web page as the designer intended. The user can select different browser software and browser options, use different network software and on-line service, and run other concurrent applications. We execute the application under every browser/platform combination to ensure the web sites work properly under various environments.

7. Reliability and Availability Testing
A key requirement o a website is that it Be available whenever the user requests it, after 24-hours a day, every day. The number of users accessing web site simultaneously may also affect the site's availability.

8. Performance Testing
Performance Testing, which evaluates System performance under normal and heavy usage, is crucial to success of any web application. A system that takes for long to respond may frustrate the user who can then quickly move to a competitor's site. Given enough time, every page request will eventually be delivered. Performance testing seeks to ensure that the website server responds to browser requests within defined parameters.

9. Load Testing
The purpose of Load testing is to model real world experiences, typically by generating many simultaneous users accessing the website. We use automation tools to increases the ability to conduct a valid load test, because it emulates thousand of users by sending simultaneous requests to the application or the server.

10. Stress Testing
Stress Testing consists of subjecting the system to varying and maximum loads to evaluate the resulting performance. We use automated test tools to simulate loads on website and execute the tests continuously for several hours or days.

11. Security Testing
Security is a primary concern when communicating and conducting business- especially sensitive and business- critical transactions - over the internet. The user wants assurance that personal and financial information is secure. Finding the vulnerabilities in an application that would grant an unauthorized user access to the system is important.

what is the difference between delivarables and Release notes??
Release notes are provided for every new release of the build with fixed bugs. It contains what are all the bugs fixed and what are pending bugs.
Deliverables are provided at the end of the testing. Test plan, test cases, defect reports, documented defects which are not fixed etc come under deliverables.

what is a testcase and usecase ?
Use case is a description of a certain feature of an application in terms of actors ,actions and responses.
For example if the user enters valid userid and password and after clicking on login button the system should display home page.
Here the user is ACTOR. The operations performed by him are ACTIONS. The Systems display of home page is RESPONSE.

Actually using use cases we will write our test cases if any use cases are provided in the SRS.
A test case is a set of test inputs,executional conditions,with some expected results developed for validating a particular functionality of AUT.

How can you say that you have done good testing?
Good testing can be done.... but complete testing cannot be... Common factors in deciding good
testing are
1.Test cases completed with certain percentage passed.
2.Coverage of code/functionality/requirements reaches a specified point
3.) Bug rate falls below a certain level 4) Beta or alpha testing period ends


Difference between defect severity and defect priority?
Defect Severity : The damage(or)effect of the defect on the Particular application.
Ex:
Fatal-System crash,System Shutdown,System Restarting...etc
Major-Internal errors,one module completely blocked....etc
Minor-Validations,Functions Miss placement.....etc
Cosmetic-Spelling mistakes......etc

Change Request-requesting for any functionality & nbsp; &nb sp; changes,objects changes.....etc

Defect Priority :Levels of the Defect to be solved by the developer
High Priority-defect Should be solved right now.
Medium Priority-Not so important,but Developer should solve it at any cost of time.

When will we give severity priority for bugs in bug report?
While executing the application if we found any functionality is not working as per the requirements then we will specify the severity based on the affect of the defect on the application. But priority is given by the test manager or test lead or project manager .


What type of test scenario's will you write for a web testing project?
Verify the URL of Web application.
verify the Login and Password credential.
verify the validation on login page by using test data.
verify the static and dynamic text filed and also hyperlinks.
verify the alignment and overlap screen on web application.
verify the sanity testing for further process on system testing.


what is three way traceability matrix?
A three way traceability matrix is the document contains the requirements, test cases and defects if any.(mapping of all these).


What is test Metrics?
Test metrics consist of:
•Total test
•Test run
•Test passed
•Test failed
•Tests deferred
•Test passed the first time


Types of Testing

Black box testing - Internal system design is not considered in this type of testing. Tests are based on requirements and functionality.

White box testing - This testing is based on knowledge of the internal logic of an application’s code. Also known as Glass box Testing. Internal software and code working should be known for this type of testing. Tests are based on coverage of code statements, branches, paths, conditions.

Unit testing - Testing of individual software components or modules. Typically done by the programmer and not by testers, as it requires detailed knowledge of the internal program design and code. may require developing test driver modules or test harnesses.

Incremental integration Testing - This is continuous testing of an application when a new functionality is added the existing ones; it checks the application functionality by verifying whether it works separately before all parts of the program are completed, in this type it will be checked whether to introduce test drivers or not; this is done by programmers or by testers.

Integration testing - This testing is combining the ‘parts’ of an application to determine if they function together correctly. The 'parts' can be code modules, individual applications, client and server applications on a network, etc. This type of testing is especially relevant to the client/server and distributed systems.

Functional testing - This type of testing ignores the internal parts and focus on the output is as per requirement or not. Black-box type testing geared to functional requirements of an application.

System testing - Entire system is tested as per the requirements. Black-box type testing that is based on overall requirements specifications, covers all combined parts of a system.
OR
System testing of software or hardware is testing conducted on a complete, integrated system to evaluate the system's compliance with its specified requirements. System Testing is a more limiting type of testing; it seeks to detect defects both within the “inter-assemblages” and also within the system as a whole.

End-to-end testing - Similar to system testing, involves testing of a complete application environment in a situation that mimics real-world use, such as interacting with a database, using network communications, or interacting with other hardware, applications, or systems if appropriate.

Sanity testing - Testing to determine if a new software version is performing well enough to accept it for a major testing effort. If application is crashing for initial use then system is not stable enough for further testing and build or application is assigned to fix.

Regression testing - Testing the application after a change in a module or part of the application for testing that is the code change will affect rest of the application.
Re- test - Retesting means we testing only the certain part of an application again and not considering how it will effect in the other part or in the whole application.

Acceptance testing -Normally this type of testing is done to verify if system meets the customer specified requirements. User or customer do this testing to determine whether to accept application.

Load testing - Its a performance testing to check system behavior under load. Testing an application under heavy loads, such as testing of a web site under a range of loads to determine at what point the system’s response time degrades or fails.

Stress testing - System is stressed beyond its specifications to check how and when it fails. Performed under heavy load like putting large number beyond storage capacity, complex database queries, continuous input to system or database load.

Performance testing - Term often used interchangeably with ’stress’ and ‘load’ testing. To check whether system meets performance requirements. Used different performance and load tools to do this.

Usability testing - This testing is done to check the 'user-friendliness' of the application. This depends on the targeted end-user or customer. User interviews, surveys, video recording of user sessions, and other techniques can be used. Programmers and testers are usually not appropriate as usability testers.

Install/uninstall testing - Tested for full, partial, or upgrade install/uninstall processes on different operating systems under different hardware, software environment.

Recovery testing - Testing how well a system recovers from crashes, hardware failures, or other catastrophic problems.

Security testing - It is a process used to look out whether the security features of a system are implemented as designed and also whether they are adequate for a proposed application environment. This process involves functional testing, penetration testing and verification.

Installation testing - Installation testing is done to verify whether the hardware and software are installed and configured properly. This will ensure that all the system components were used during the testing process. This Installation testing will look out the testing for a high volume data, error messages as well as security testing.

Compatibility testing - Testing how well software performs in a particular hardware/software/operating system/network environment and different combination s of above.

Comparison testing - Comparison of product strengths and weaknesses with previous versions or other similar products.

Alpha testing - In house virtual user environment can be created for this type of testing. Testing is done at the end of development. Still minor design changes may be made as a result of such testing.

Beta testing - Testing typically done by end-users or others. Final testing before releasing application for commercial purpose.

Static testing - Is a form of software testing where the software isn't actually used. This is in contrast to Dynamic testing. It is generally not detailed testing, but checks mainly for the sanity of the code, algorithm, or document. It is primarily syntax checking of the code or and manually reading of the code or document to find errors. This type of testing can be used by the developer who wrote the code, in isolation. Code reviews, inspections and walkthroughs are also used.

Dynamic testing (or dynamic analysis) - Is a term used in software engineering to describe the testing of the dynamic behavior of code. That is, dynamic analysis refers to the examination of the physical response from the system to variables that are not constant and change with time.

Negative testing - Testing the system using negative data is called negative testing, e.g. testing the password where it should be minimum of 8 characters so testing it using 6 characters is negative testing.

Ad hoc testing - Ad hoc testing is concern with the Application Testing without following any rules or test cases. For Ad hoc testing one should have strong knowledge about the Application.

Soak Testing - Running a system at high load for a prolonged period of time. For example, running several times more transactions in an entire day (or night) than would be expected in a busy day, to identify and performance problems that appear after a large number of transactions have been executed.

Describe bottom-up and top-down approaches in Regression Testing.
Bottom-up approach : In this approach testing is conducted from sub module to main module, if the main module is not developed a temporary program called DRIVERS is used to simulate the main module.
Top-down approach : In this approach testing is conducted from main module to sub module. if the sub module is not developed a temporary program called STUB is used for simulate the submodule.


Explain Load, Performance, Stress Testing with an example
Load Testing and Performance Testing are commonly said as positive testing where as Stress Testing is said to be as negative testing.
Say for example there is a application which can handle 25 simultaneous user logins at a time. In load testing we will test the application for 25 users and check how application is working in this stage, in performance testing we will concentrate on the time taken to perform the operation. Where as in stress testing we will test with more users than 25 and the test will continue to any number and we will check where the application is cracking the Hardware resources.

Will come soon with more concepts.........