Audit Trail

 Definition(s):

  1. A chronological record that reconstructs and examines the sequence of activities surrounding or leading to a specific operation, procedure, or event in a security relevant transaction from inception to final result.
  2. A record showing who has accessed an information technology (IT) system and what operations the user has performed during a given period.

 Source: CNSSI-4009

Merriam-Webster Online Dictionary
audit trail (noun)
a record of a sequence of events (as actions performed by a computer) from which a history may be reconstructed
An audit trail is a chronological record of system activities that is used to trace the sequence of events and to help detect unauthorized use or modifications of information. It is a security tool used to monitor and track changes made to a system, such as user logins, file access, and other system activities.