File Name: en_windows_7_professional_with_sp1_x64_dvd_621750.iso
Date Published (UTC): 2/16/2011 8:49:08 AM Last Updated (UTC): 2/16/2011 8:49:08 AM
SHA1: 5ED2584110E03F498DB4458BA9FAFD5A7EF602ED ISO/CRC: 74F3CB73
With this information, I can be confident in downloading an ISO from a peer-to-peer torrent. When the hash matches, I can be assured that the file is legit and not backdoored.
You probably mean "clerical"?