Methodology of Software Quality Assurance

Software testing is as much an art as a science. In large, complex applications, such as operating systems, it is practically impossible to iron out every single bug before releasing it both from a difficulty point of view and due to time constraints. Different software applications require different approaches when it comes to testing, but some of the most common tasks in software QA include:

PPQA audits
Process and Product Qualty Assurance is the activity of ensuring that the process and work product conform to the agreed upon process.
The following quality control activities are often confused as quality assurance activities:

Peer Reviews
Peer reviews of a project's work products are the most efficient defect removal (quality control) activity.

Validation testing
Validation testing is the act of entering data that the tester knows to be erroneous into an application. For instance, typing "Hello" into an edit box that is expecting to receive a numeric entry.

Data comparison
Comparing the output of an application with specific parameters to a previously created set of data with the same parameters that is known to be accurate.

Stress testing
A stress test is when the software is used as heavily as possible for a period of time to see whether it copes with high levels of load. Often used for server software that will have multiple users connected to it simultaneously. Also known as Destruction testing.

Usability testing
Sometimes getting users who are unfamiliar with the software to try it for a while and offer feedback to the developers about what they found difficult to do is the best way of making improvements to a user interface.