Top-down testing is a mechanism that, by setting up a central location for
the modification of test documentation and test execution, provides for close proximity
of the text execution and the description of the test. In particular, by providing
assertions which point to the line of end user documentation being tested, as well
as the associated test script code, top-down testing enables a tester easily trace
back to the origin in the end user documentation reference. In addition, the tester
can quickly become productive with little product knowledge or test expertise.