When Testimony records activity in a system, it captures inputs, outputs and certain linkages that occur in-between. When the playback is executed in the test system, Testimony will automatically check that the output in the playback matches the output that was received in the recording. If linkages (for example, change documents) were recorded, it will compare these as well. Once a playback has completed, there are various ways of reviewing the results of the playback. These are described in the following sections.