Software Testing

What is software testing and why we need to test an application before it goes to implementation or go Live ?


software testing is carried out a study to allow interested parties information on the quality of the product or service to be tested.  Software Testing provides an objective, independent view on the software to evaluate the economy and understand the risks associated with the implementation of the software. analysis techniques include but not limited to, the process of executing a program or application with the intent of finding bugs in software.

test software can be used as the process of validation and verification, as a software / application / product will be indicated:

   1 are the operational and technical requirements that guide the design and development;
   2nd works as expected, and
   3 May be made with the same characteristics.

Software Testing, depending on the method used can always be put into the development process. However, most of the effort comes after the test conditions were defined and the coding is completed. declared as such, the methodology of the review by the software development methodology is adopted.

Several models of software development, testing effort at various points in the development process of development. The new development models like Agile, often use test-driven development and place a greater portion of the test in the hands of developers before reaching an official of the test team. In a more traditional, more testing occurs after the conditions have been identified and the coding is completed.


Tests may never completely identify defects in software. Instead, it provides a criticism or comparison that could be the state and behavior of the product against oracles, principles or mechanisms to recognize a problem with someone who compares. These include Oracle may include (but are not limited to) specifications, contracts, comparable , the products, the latest versions of the same product, inferences about intended or should be, the user or customer expectations, standards relevant legislation or other criteria.

Each program has a target audience. For example, the audience for video game software banking software completely. Therefore, if an organization or invested in the development of a software product, we can judge whether the software product is acceptable, and their end customers, target audience, ITS customers and other stakeholders. Software Testing is the process of trying to make this assessment.

A study conducted by NIST in 2002 reports that software bugs cost the U.S. economy 59.5 billion U.S. dollars annually. More than one third of these costs could be avoided if better software testing to be performed.


What is the scope of the test?

One of the main objectives of the review is to errors in the software so that defects can be detected and identified correctly. This is a Non-Trivial Pursuit. The test can determine if a product works properly in all conditions, but can only note that does not work correctly under certain conditions.  The scope of software testing often includes a code review and enforcement of the code in different environments and conditions, and examining aspects of the code: it does what it should do and what to do. In the current culture of software development, an organization can test by the development team to divide. There are different roles for testing team members. Information for software testing can be used to correct the process, developed by software.


Tests functional or not functional

Functional testing includes tests that verify an action or a specific function code. They are usually found in the documentation requirements of the Code, although certain methods of development of use cases or user stories. Functional tests tend to place the issue of "the user can do this" or answer ", this feature of the work."

Test refers to non-functional aspects of software can not access a function or a specific user, such as scalability or security. Non-functional tests tend to answer questions like "How many people can be both," and "How easy is to hack the software.

***** The defects and faults

Not all software defects are caused by coding errors. A common cause of costly errors caused by deficiencies in the application, for example, requirements that lead to unknown errors in the failure of the design program. [14], a common source of the difference in requirements is non-functional requirements such as testability, scalability, maintainability, usability, performance and safety.

software errors occur through the following processes. A programmer makes an error (error) that the defect (error, error) causes the source code. If this error is common in some situations, the system produces incorrect results, causing a failure. [15] are not all defects will inevitably lead to errors. For example, the defects of dead code will never lead to failures. A deficiency can lead to failure if the environment changes. Examples of these include changes in the software on a new hardware platform running, changes to the source data or interacting with other software. An error can cause a variety of deficits.

static and dynamic testing

There are many methods of software testing. Reviews, walkthroughs, or inspection are considered static tests, when in fact the execution of code is programmed with a certain amount of test cases, known as dynamic testing. Static testing can be (and, unfortunately, the practice is often omitted). Dynamic test occurs when the program first (which is generally regarded as the beginning of the trial period is used). Dynamic tests can begin before the program is 100% complete, to test parts of code (modules or discrete functions). Typical of these techniques are either the husband or the driver or the execution of a debugger environment. For example, spreadsheet, which by their nature, tested interactively in large part (on the fly "), the results are displayed immediately after each calculation or manipulation of the text.


Verification and validation

software testing is used in conjunction with the control and  validation

    * Re: we are building the right software? (In other words, it meets the specifications).
    * Validation: we built the right software? want (ie what the customer).

Verification and validation of the terms are often used interchangeably in the industry, is also common to see these two concepts are defined incorrectly. According to the glossary of terminology IEEE Software Engineering:

    Verification is the process of evaluating a system or component to determine if the product of specific conditions has led to the development phase of this meeting.
    Validation is the process of evaluating a system or component during or at the end of the development process to determine if it meets certain requirements.


Software Quality Assurance (SQA)

Although the software testing issue as an important part of software quality assurance (SQA) process.  is SQA, software process specialists make and has a broader view on software and its development. Check and modify the software engineering process itself, the number of errors that reduce the end came with the software: the error rate.

What makes an "acceptable error rate" depends on the type of software. For example, to simulate a video game arcade, flying an airplane, you probably have a much higher tolerance for defects of Mission Critical Software, so that E 'used to steal the functions of a plane that is actually designed for control!

Although there are close links with SQA, testing departments often exist independently, and there can be no SQA function in some companies.

Software Testing is a task to detect flaws in the software of a computer program by the juxtaposition of the expected results with actual results for a given set of inputs. In contrast, QA (Quality Assurance) implementation of policies and procedures to prevent the occurrence of defects in the first place.