Circumstantial evidence is defined as inference of information from other, intermediate, relevant facts. Secondary evidence is a copy of evidence or oral description of its contents. Conclusive evidence is incontrovertible and overrides all other evidence and hearsay evidence is evidence that is not based on personal, first-hand knowledge of the witness, but was obtained from another source. Computer-generated records normally fall under the category of hearsay evidence. Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 9: Law, Investigation, and Ethics (page 310).