BACKGROUND

If you were buying a new car, you would not expect to take delivery from the showroom with a scratch down the side of the vehicle. The car should have five wheels, a steering wheel, an engine and all the other essential components, and it should come with appropriate documentation, with all pre-sales checks completed and passed satisfactorily. The car you receive should be the car described in the sales literature; it should have the correct engine size, the correct colour scheme, and whatever extras you have ordered, and performance in areas such as fuel consumption and maximum speed should match published figures. In short, a level of expectation is set by brochures, by your experience of sitting in the driving seat, and probably by a test drive. If your expectations are not met you will feel justifiably aggrieved.

This kind of expectation seems not to apply to new software installations; examples of software being delivered not working as expected, or not working at all, are common. Why is this? There is no single cause that can be rectified to solve the problem, but one important contributing factor is the inadequacy of the testing to which software applications are exposed.

Software testing is neither complex nor difficult to implement, yet it is a discipline that is seldom applied with anything approaching the necessary rigour to provide confidence in delivered software. Software testing is costly in human effort or in the technology that can multiply the effect of human effort, yet is seldom implemented at a level that will provide any assurance that software will operate effectively, efficiently or even correctly.

This book explores the fundamentals of this important but neglected discipline to provide a basis on which a practical and cost-effective software testing regime can be constructed.