ALSO CALLED: Clear Box Testing, Glass Box Testing, and Structural Testing
DEFINITION:

A white box or clear box is a device, program or system whose internal workings are well understood. White box testing, also called white box analysis, clear box testing or clear box analysis, is a strategy for software debugging in which the tester has excellent knowledge of how the program components interact and also is familiar with the details of its internal operation.

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WHITE BOX TESTING DEFINITION (continued): …  box testing can be used for Web services applications early in the development cycle. This method is rarely practical for debugging in large systems and networks because it is difficult or impossible to access the source code. In these cases, gray box testing is more often used. The Internet is a complex system with variable and evolving components but well-known and relatively stable interfaces.

White box testing is highly effective in detecting and resolving problems because bugs can often be found before … 
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