What is Quality Assurance?
Software quality assurance is the process of enforcing quality control standards and working to improve processes that are used in producing software application components, technical infrastructure and application content. Successful implementation of software quality assurance processes means an application will pass tests more consistently, allowing metrics to be refined. Quality assurance is focused on process improvement and the ultimate goal of quality assurance, is to improve output quality by improving the downstream processes.
Quality assurance should be viewed as the "voice of the customer", reminding the software development team that the application is to be used outside the team and current environment. Understanding quality assurance means understanding the importance of process and the importance of the ultimate customer.
Quality assurance has a wider scope than quality control because test cases created in the quality control phase are necessarily limited. Quality assurance focuses on the ability of the application to meet specific benchmark criteria.
Quality assurance should be involved from the start of the design process. All aspects of the application and surrounding processes are continually evaluated with the aim of improving output and input quality. Often, many of the usability factors will not become apparent until the development of testing process and valuable time and rework will be required. With actual user input, quality assurance teams are able to refine user scenarios to mirror actual rather than assumed, user behaviour - there is no substitute for 'real' user input.
What is Quality Control?
Quality control focuses on what comes out of a process and describes the process of measuring whether an objective has been met or not.
Quality control is the process of analysing exactly what the application should do and preparing a strategy to check these objectives. Tumarc achieves this by using a series of structured process steps, geared towards application testing - using comprehensive documentation at every stage. The key stages are:
- Defining the business and functional requirements of the application
- Measuring the current application performance against the requirements
- Analysing the application to produce a structured test strategy including any limits that the tests themselves may have
- Creation of structured test cases based on the information agreed from the analysis phase using defined success and failure criteria
- Execution of the test strategy
- Control processes to perform regression testing and maintenance testing
Test cases and test plans are an example of quality control processes because structured planning is used to test whether an application is performing within the defined limits.
Quality control sets the standards for applications but is a reactive process - it does nothing to improve the processes and quality of the application. This improvement process is all part of Quality Assurance.
What is Testing?
Quality assurance, quality control and testing are often confused. It is important to understand the differences.
Testing is the process of creating a test case, executing the test and evaluating the test against a defined benchmark or set of criteria at each step of the process. In most cases, a well planned test should have a defined scope; set criteria that the test must meet in order to pass and a defined period where the testing will take place.
Testing is reactive because the process is attempting to find instances where the application does not perform as specified. By employing a systematic set of test cases, an application should have a measurable quality - presuming that the planning behind the test cases has covered the scope correctly.
Ultimately, testing will not raise the quality of the application beyond what has been specified. It will only ensure that what has already been specified, functions to the highest possible level within a defined scope.
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