A visitor log is the record of every non-employee who enters the building: who they were, who they came to see, and when they arrived and left. Reception uses it to issue badges, hosts use it to know a guest has arrived, and in an evacuation the fire warden uses it to confirm every visitor is out. The
visitor log entry in the glossary covers the legal side; the short version is that the record needs to be accurate, kept for a defined period, and not left open on the desk for the next visitor to read.