4.1 Categories of Test Techniques

The purpose of a test technique, including those discussed in this section, is to help in identifying test conditions, test cases, and test data.

The choice of which test techniques to use depends on a number of factors, including:

• Component or system complexity

• Regulatory standards

• Customer or contractual requirements

• Risk levels and types

• Available documentation

• Tester knowledge and skills

• Available tools

• Time and budget

• Software development lifecycle model

• The types of defects expected in the component or system

Some techniques are more applicable to certain situations and test levels; others are applicable to all test levels. When creating test cases, testers generally use a combination of test techniques to achieve the best results from the test effort.

The use of test techniques in the test analysis, test design, and test implementation activities can range from very informal (little to no documentation) to very formal. The appropriate level of formality depends on the context of testing, including the maturity of test and development processes, time constraints, safety or regulatory requirements, the knowledge and skills of the people involved, and the software development lifecycle model being followed.